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, Will Cantine and Jordan Mazza

UKRAINE VIOLENCE ABC News' Serena Marshall, Jim Avila and Mary Bruce: " Obama Warns Kiev It Is 'Responsible' For Avoiding Bloodshed" President Obama interrupted his North American Summit visit to Mexico to say he hopes an announced truce in the Ukraine holds long enough to give the government and the opposition time to step back from violence and work on peace. "If the truce is implemented it could provide space for the sides to resolve their disagreements peacefully and going forward we will continue to do whatever we can to support Ukrainians as they seek a peaceful solution and respond to the aspirations of the Ukrainians people for a strong unified democracy that is fully integrated in with the international community," Obama said. LINK

ABC News' Arlette Saenz and Mary Bruce: " Obama Threatens 'Consequences' For Violence In Ukraine" President Obama today condemned the violence occurring in Ukraine and warned there would be "consequences" if the brutality continues. "The United States condemns in the strongest terms the violence that's taking place. And we have been deeply engaged with our European partners as well as the Ukrainian government and the opposition to try to ensure that that violence ends," the president said shortly after he arrived here for the North American Leaders Summit. LINK

The Wall Street Journal's Jared A. Favole, Adam Entous and Carol E. Lee: " Obama Condemns Ukraine Violence, Warns Of 'Consequences'" U.S. President Barack Obama condemned the violence in Ukraine, warning the government on Wednesday that "there will be consequences if people step over the line." Mr. Obama said the U.S. is in contact with European leaders about a way forward. "We hold the Ukrainian government primarily responsible," Mr. Obama said upon arriving in Mexico for a three-way summit with Canadian and Mexican leaders. "There is still the possibility of a peaceful transition." LINK

The Hill's Julian Pecquet and Justin Sink: " Obama strongly condemns 'unacceptable violence' in Ukraine" President Obama said Wednesday he was hopeful that a declared truce in Ukraine could provide "space" for peace talks after a whirlwind day that saw U.S. and European leaders threaten to impose sanctions against the government of President Viktor Yanukovych. "We've obviously seen reports of a truce between the government and the opposition," Obama said at a summit with Canadian prime minister Stephen Harper and Mexican President Pena Nieto. "If the truce is implemented, it could provide space for the sides to resolve their disagreements peacefully." LINK

NSA The Los Angeles Times' Seema Mehta: " Sen. Dianne Feinstein defends NSA and need for intelligence gathering" Sen. Dianne Feinstein (D-Calif.) offered a full-throated defense of the government's collection of data on billions of American phone calls, saying Wednesday that the National Security Agency's practices have safeguarded the nation without trampling on civil liberties. "What keeps me up at night, candidly, is another attack against the United States. And I see enough of the threat stream to know that is possible," Feinstein said at a Pacific Council on International Policy dinner in Century City. LINK

FEDERAL WORKERS The New York Daily News' Adam Edelman: " Federal employees have worked less than 75% of days they were supposed to since Oct. 1: report" Federal workers have actually worked for less than three-quarters of the days they were supposed to since Oct. 1, a new reports alleges. Due to snow days, official holidays and the government shutdown, U.S. government employees have shuttered their offices in whole or in part for 27 of the 105 weekdays since the fiscal year began at the start of October, a Washington Times review of scheduling announcements from the federal Office of Personnel Management showed. LINK

ARMY RIFLE The Washington Times' Rowan Scarborough: " Troop left to fend for themselves after Army was warned of flaws in rifle" Army Senior Warrant Officer Russton B. Kramer, a 20-year Green Beret, has learned that if you want to improve your chances to survive, it's best to personally make modifications to the Army's primary rifle - the M4 carbine. Warrant Officer Kramer has been dropped into some of the most ferocious battles in the war on terrorism, from hunting Islamists in the mountains of northern Iraq to disrupting Taliban opium dealers in dusty southern Afghanistan. He was awarded the Silver Star for his bravery in Operation Viking Hammer to crush the terrorist group Ansar al-Islam in Iraq. LINK

KEYSTONE PIPELINE USA Today's Aamer Madhani: " Obama Defends Lengthy Vetting Process For Keystone XL" President Obama on Wednesday defended the protracted process his administration is using to decide whether to approve the Keystone XL pipeline. Obama's comments, made with Canada's Prime Minister Stephen Harper by his side, are his first on the pipeline since a State Department report issued earlier this month concluded the pipeline will have a negligible impact on climate because expanded development of carbon-heavy tar sands of northwest Canada is inevitable, with or without the pipeline. LINK

The Wall Street Journal's Alison Sider and Alicia Mundy: " Nebraska Judge Blocks Governor's Keystone XL Decision" A Nebraska judge ruled Wednesday the law allowing the controversial Keystone XL oil pipeline to be built across the state is unconstitutional, a move that could further delay the project. Lancaster County District Court Judge Stephanie Stacy sided with three landowners who argued Nebraska's governor shouldn't be able to sign off on the pipeline's route. The governor, Republican Dave Heineman, was handed that power in a law the state Legislature hastily passed in 2012. But the court ruled that under the state's constitution, only Nebraska's Public Service Commission could approve such a pipeline route. LINK

ABC NEWS VIDEO " Venezuelan Opposition Leader's Arrest Intensifies Protests" LINK " Obama: 'The Ukrainian People Are Able To Assemble Without The Fear Of Repression'" LINK " Yes, That's Prince Charles Dancing With A Sword" LINK " Drone Gives Dramatic View Of Ukraine Chaos" LINK " Soldiers Mugging With Casket Is An 'Outrage,' Wis. Governor Says" LINK

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