The Note's Must-Reads are a round-up of today's political headlines and stories from ABC News and the top U.S. newspapers. Posted Monday through Friday right here at www.abcnews.com

Compiled by ABC News' Jayce Henderson, Jordan Mazza and Janine Elliot

RUSSIA/UKRAINE ABC News' Adam Teicholz: " Samantha Power: Putin's Actions Suggest He Wants Eastern Ukraine " In a wide-ranging, exclusive interview with George Stephanopoulos this morning on "This Week," U.S. Ambassador to the United Nations Samantha Power had harsh words for Russian President Vladimir Putin in the wake of pro-Russian soldiers' recent takeovers of government buildings in several eastern Ukrainian cities. Asked by Stephanopoulos if the U.S. believes that Putin "wants" Eastern Ukraine, Power responded, "I think the actions that he is undertaking certainly give credence to that idea. But I will say in the conversations that we have, of course, they keep insisting, 'No, that's not what we want, that's not what we want.' But everything they're doing suggests the opposite." LINK

Wall Street Journal's James Marson: " Ukraine Orders Troops East as Pro-Russian Forces Extend Grip" Pro-Russian activists and militants extended their grip across eastern Ukraine, prompting the government to mobilize the military as it struggled to prevent a replay of Russia's takeover of Crimea. The U.S. and its Western allies said some of the well-equipped gunmen who participated in seizing police stations and other buildings in several cities and towns over the weekend appeared to be Russian special forces in unmarked uniforms. Such troops moved into Crimea shortly before the region voted to secede from Ukraine and was annexed by Moscow last month. LINK

USA Today's David Jackson: " Obama Aide: Russia may be involved in Ukraine violence" A top aide to President Obama says there are signs of Russia involvement in new violence in eastern Ukraine. Samantha Power, U.S. ambassador to the United Nations, told ABC's This Week that gun battles between Ukraine troops and Russian protesters resemble events that preceded Russia's annexation of Crimea. "It's professional, it's coordinated - there's nothing grass roots-seeming about it," Power said. "So certainly it bears the tell-tale signs of Moscow's involvement." LINK

IRAN ABC News' Freda Kahen-Kashi: " Sen. Rand Paul weighs containment of Iran Nuclear threat" Sen. Rand Paul, R-Ky., told ABC News' Jonathan Karl he believes "all options should be on the table" to prevent a nuclear Iran, but the U.S. should not immediately accept the idea of war when the threat of a nuclear Iran could be contained as it has been with other nuclear powers. "I've repeatedly voted for sanctions against Iran. And I think all options should be on the table to prevent them from having nuclear weapons," Paul said on "This Week" Sunday. But he said those who oppose the idea of containment - or living with an Iran with nuclear weapons - ignore that such an outcome has been necessary in the past. LINK

Wall Street Journal's Jay Solomon: " Iran's Leaders Still Touting Nuclear Progress" A senior cleric delivering a nationally televised sermon urged a crowd that included former President Mahmoud Ahmadinejad and the head of Iran's nuclear energy organization to observe sexual piety, aid the poor and support Iran's development of nuclear power. "This technology is progressing our nation," Ayatollah Imami Kashani said at weekly Friday prayers at the University of Tehran. "Our enemies are against such progress." The sermon, like other speeches and television appearances by senior leaders recently, offered few signs the government is conditioning Iranians for any major limitations on nuclear work. LINK

KANSAS SHOOTING The Hill's Kyle Balluck: " Obama: Kansas shootings 'horrific'" President Obama late Sunday offered condolences to families who lost loved ones in shootings in suburban Kansas City.Three people died at a Jewish community center and an assisted living facility, according to multiple reports. "This afternoon we heard reports of a horrific shooting in Overland Park, Kansas," Obama said in a statement. "Michelle and I offer our thoughts and prayers to the families and friends who lost a loved one and everyone affected by this tragedy." LINK

HEALTH & HUMAN SERVICES SECRETARY KATHLEEN SEBELIUS The Washington Times' Tom Howell Jr.: " HHS nominee Burwell faces tight scrutiny" Lawmakers dug in Sunday for a proxy war over the new health care law, now that President Obama has selected a well-known manager to replace Health and Human Services Secretary Kathleen Sebelius and lead his signature program into a new era. Mr. Obama says his budget chief, Sylvia Mathews Burwell, is a "proven manager" who will lead HHS with distinction and build on whatever momentum the White House gained by signing up 7.5 million Americans in private health coverage from October to March. LINK

The New York Daily News' Adam Edelman: " Former HHS Secretary Kathleen Sebelius says she was 'flat-out wrong' to think Obamacare site was ready to go in October" Former Health and Human Services Secretary Kathleen Sebelius, who stepped down last week following the clunky rollout of Obamacare, said Sunday she was "flat-out wrong" to think that the government health care site was ready for launch last October. "The launch of the website was terribly flawed, terribly difficult," Sebelius said on NBC's "Meet the Press." "Could we have used more time and testing? You bet." LINK

The Los Angeles Times' David Savage: " Sebelius praises Obamacare, concedes rollout was botched" Outgoing Health and Human Services Secretary Kathleen Sebelius said Sunday that the health insurance exchanges that are now up and running across the country have given uninsured Americans a true choice of insurance plans with price comparisons. "People have competitive choices and real information for the first time ever in this insurance market," Sebelius said in an interview on NBC's "Meet The Press." LINK

BOSTON BOMBING MARATHON ANNIVERSARY ABC News' Benjamin Bell: " Gov. Deval Patrick: 'Very Thorough' Planning to Protect Boston Marathon" "I think we are very well prepared and people should come out and enjoy themselves," Patrick said this morning on "This Week." "I think we have struck an appropriate balance between having more law enforcement presence, but also assuring that it continues to be a family outing and a civic ritual," he told ABC's George Stephanopoulos. "The planning has been very, very thorough. The teams are well coordinated. … We had a sort of table-top exercise, a practice session, a full day, a couple of weeks ago with there were 450 people in the room from every state, federal and local agency and municipal leadership, as well, for each of the cities and towns along the route," he continued. LINK

Rep VANCE McALLISTER The New York Times' Trip Gabriel: " Amid Charges of Hypocrisy, Louisiana Lawmaker Faces Calls to Step Down " As she handed out garbage bags on Saturday as part of an anti-litter drive, Patsy Edmondson drew a parallel to Louisiana's history of tawdry politics. "If we grow up in litter, we accept it," she said. LINK

DEMOCRATS The Washington Post's Wesley Lowery: "Democrats settle on fairness issues hoping to avoid a repeat of 2010 midterm disaster" On the defensive about their prospects in the midterm elections this fall, congressional Democrats have spent all of April savaging the Republican budget proposal, decrying the Koch brothers and championing a series of bills meant to ingratiate themselves to struggling middle-class voters. In promoting legislation that would extend unemployment benefits, increase the minimum wage and promote equal pay for women, the Democrats have declared themselves the party that will ensure a "fair shot" for all. LINK

OTHER Politico's Edward-Isaac Dovere: " How the Obama peace process went 'poof'" Over chicken wings back at the hotel after the official dinner the king of the Netherlands hosted at the start of their trip to Europe last month, President Barack Obama, Secretary of State John Kerry and national security adviser Susan Rice tried to figure out how to save the peace process. They met again that Friday en route to Riyadh on Air Force One, looking for an answer. LINK

ABC NEWS VIDEO: " 'This Week': Crisis in Ukraine" LINK " 'This Week': Samantha Power on Ukraine" LINK " 'This Week': Sen. Rand Paul" LINK " 'This Week': Powerhouse Roundtable" LINK " 'This Week': Powerhouse Puzzler" LINK " 'This Week': Sebelius Steps Down" LINK " 'This Week': Remembering Rwanda LINK

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