Japanese Prime Minister Shinzo Abe visits White House ahead of G-20 summit in Osaka

Golf, gold-plated gifts, steak dinners and red carpet invitations -- President Donald Trump may know the art of the deal, but Japanese Prime Minister Shinzo Abe probably leads when it comes to the art of flattery.

On Friday, Abe and Trump met at the White House for high-stakes talks on the upcoming G-20 summit, as well as trade, China and North Korea.

The president welcomed the prime minister to the White House and, sitting in the Oval Office, Trump expressed optimism that the United States and Japan will strike a deal.

"I think a lot will be accomplished," Trump said. "We have a chance to make a very good and long term trade deal with Japan."

But as with all meetings between Abe and Trump, there will be personal touches.

Friday night, the Abes will join the Trumps for dinner to celebrate first lady Melania Trump's birthday.

The president said he asked the first lady if she would like to have the Abes them join for dinner.

"I can’t think of anybody I’d rather have," the first lady replied, he recalled.

And on Saturday, Trump and Abe will play golf together.

However, while Abe gets unusually personal gestures from the president -- who calls him a "good friend" -- it's unclear, so far, what Japan has earned from the leaders' close personal relationship. Instead, the longtime U.S. ally is facing U.S. tariffs, was forced into trade talks and fears being iced out of North Korea negotiations.

"Abe has tried harder than any other world leader to ingratiate himself with Trump. But the question that the Japanese are asking is, 'Well, to what end? What has Japan achieved?'" said Shihoko Goto, a Japan expert at the Wilson Center.

Because of that, Japan also has worked to strengthen relationships elsewhere. Before visiting Washington, Abe stopped in Brussels for a summit with European Union leaders after Japan and the E.U. finalized the world's largest trade deal, which went into effect in February. Abe has also turned to old adversaries, such as China and Russia. He made his first visit to Beijing in October and is preparing for Chinese President Xi Jinping's first visit to Japan in June. It's the first visit by a Chinese leader in over a decade.

Still, Japan places great importance on its close relationship with the U.S., and the bond its prime minister has built with Trump. While Japanese officials said the focus of Friday's visit is to prepare for the G-20 summit Japan's hosting in June, it also gives Abe another chance to work on that bond -- and perhaps win something from it.

"Whatever happens, whatever the challenge may be, they always keep in touch with each other and that will contribute a lot to the betterment of the bilateral relationship," a Japanese official told ABC News. "Not only Prime Minister Abe, but also the Japanese people appreciate such a friendship between the two leaders."

Abe's effort to develop a close relationship with the president started right after his election. Two days after Trump's election, Abe was the first world leader to call to congratulate him. Trump has met with Abe and they have talked on the phone more than any other leader -- a total of 29 phone calls and 10 in-person meetings, according to the Japanese embassy in Washington.

Trump, who likes Abe’s charismatic style and negotiating skills, even invited Abe to be the first world leader to visit his private club Mar-a-Lago. The two joked with each other on the golf course and worked to respond to a missile test by North Korea's Kim Jong Un during an alfresco meal.

The president will be visiting Abe twice in May and June.

The president said he wanted to come visit Tokyo after Abe told him the emperor's abdication ceremony -- which hasn't happened for over two hundred years -- would be "a hundred times" bigger than the Super Bowl.

"I said, I'll be there, if that's the case," Trump said. "I'll be there ... a very unusual thing."

Trump also spoke of plans to see a sumo wrestling match in Tokyo.

"I've always found that fascinating," Trump said, and added that the United States is creating a special trophy for the winner of the wrestling match that will be presented.

Despite lavish invitations and friendly phone calls, Abe does not have much to show for his efforts, experts have said. Trump pulled out of the Trans-Pacific Partnership -- an important trade deal Abe championed -- slapped steel and aluminum tariffs on Japan, threatened tariffs on Japanese auto imports like Toyota and Nissan, and forced Abe to begin negotiations on a bilateral trade deal -- something Japan doesn't want.

"He has not convinced Trump of a lot of things he wishes the U.S. would do," said Mike Green, senior vice president for Asia and Japan chair at the Center for Strategic and International Studies. "But Abe goes into these meetings and floods the zone to keep the relationship tight."

On that last issue, Economy Minister Toshimitsu Motegi and U.S. Trade Representative Robert Lighthizer met last week and then again on Thursday to discuss a potential agreement. Japan is the United States' fourth-largest export and import market, with over $75 billion in exports in 2017.

But after Trump pulled out of the TPP, the countries that entered the trade deal gained preferential access to Japan's agricultural markets, hitting U.S. farmers hard. The U.S. wants to change that, while Japan is hoping that the U.S. doesn't follow through on the threatened auto tariffs in addition to removing the levies on steel and aluminum.

The Japanese official told ABC News trade meetings have so far been "substantial" and "fruitful" but that results can't be prejudged. With talks ongoing, it's unclear how far into the details of negotiations Trump and Abe will go.

Friday's meetings also will be Abe's first chance to hear, in person, about Trump's summit in Vietnam with North Korea's Kim Jong Un. Trump and Abe spoke by phone shortly after talks between Trump and Kim broke off.

"If military tensions return, Japan could again be in Pyongyang’s firing line," said Sheila Smith, a senior fellow for Japan Studies at the Council on Foreign Relations.

Perhaps just as worrying to the Japanese is being left behind. While Abe has expressed an openness to his own summit with Kim, the Japanese official told ABC News there's "no sign of direct negotiations" and "we don't see its appropriate timing."

"Abe is the only regional leader not in direct communication [with Kim], and that is worrisome," Smith told ABC News. "It will be particularly worrisome if negotiations start to make progress."

Still, if Abe is sweating about it, he hasn't shown Trump. Japan continues to say it is "100%" supportive of Trump's outreach to Kim -- even going so far as to nominate him for the Nobel Peace Prize, according to Trump.

When asked to confirm that nomination, Abe demurred.

"I'm not saying that's not the fact," he said. "The Nobel Committee stipulates that it will not disclose the names of nominators and the nominees for 50 years. Hence, I refrain from commenting."