Shinzo Abe met with the president-elect at Trump Tower to sound him out after a campaign that alarmed many US allies
Trump, who has been receiving a flurry of Republican operatives at his Manhattan skyscraper since his shock victory last week, appeared to be selecting staunch backers but also considering former rivals for top jobs.
Several US media outlets reported late Thursday that Trump had offered the role of national security adviser to retired general Michael Flynn, a military intelligence officer who had been a potent surrogate for the billionaire on the campaign trail.
Japanese Prime Minister Shinzo Abe met for 90 minutes with the president-elect at Trump Tower to sound him out after a campaign that alarmed many US allies.
"As an outcome of today's discussions, I am convinced Mr Trump is a leader in whom I can have great confidence," Abe told reporters, describing a "very warm atmosphere."
But Abe, a nationalist who has struggled both to perk up Japan's economy and face the rise of China, declined to go into specifics.
Japan is one of Washington's closest allies but Trump alarmed Tokyo policymakers during the campaign by musing about pulling the thousands of US troops from the region and suggesting that officially pacifist Japan may need nuclear weapons.
Trump also vowed on the campaign trail to tear up the Trans-Pacific Partnership, a proposed vast trade pact backed by outgoing Democratic President Barack Obama and which Abe had made a top priority.
US media outlets cited sources in or close to Trump's transition team as saying that Flynn had been tapped for the national security adviser role.
It was not known if Flynn had accepted the job, which would involve advising an incoming president with no national security experience on issues including the Islamic State group, China and Russia.
A former director of the Defense Intelligence Agency in 2012-2014, Flynn has sharply criticized the Obama administration's handling of IS.
During the campaign, his vocal support for Trump gave the businessman credibility with veterans despite the then-candidate's lack of military service.
Trump also met Thursday with Senator Jeff Sessions of Alabama and hinted that he would offer a prime position to the Republican, one of the earliest supporters of Trump's once longshot campaign who shares the 70-year-old billionaire's antipathy to immigration.
The tycoon in a statement said he was "unbelievably impressed" with Sessions but had not yet made decisions on his cabinet.
MSNBC reported that Trump may also be considering one of his harshest Republican critics, Mitt Romney, as secretary of state. Trump was set to meet with the former Massachusetts governor over the weekend.
"I think Mr Romney would be quite capable of doing a number of things," Sessions told reporters after his talks with Trump.
Romney, who lost to Obama in 2012, had described Trump as vulgar, dishonest and out of line with US values, rebuking the tycoon for proposals such as banning all foreign Muslims from the United States.
Romney would bring a more orthodox Republican worldview to foreign policy. In 2012 Romney described Russia as the top geopolitical threat -- a striking contrast to Trump who has exchanged compliments with President Vladimir Putin.
Earlier reports said Trump may give the job of top diplomat to South Carolina Governor Nikki Haley, an Indian-American woman who would inject rare diversity into his team. Haley headed into Trump Tower on Thursday but did not speak to reporters.
Another name floated for the State Department has been former New York mayor Rudy Giuliani, a combative longtime backer of Trump who would likely face tough Senate scrutiny over his business dealings.
Officials at the State Department and the Pentagon said Thursday that Trump's team had reached out on the transition, easing concerns of critics who note Trump's lack of governing experience.
Trump also met 93-year-old Henry Kissinger, the apostle of realpolitik who guided foreign policy for presidents Richard Nixon and Gerald Ford, and with Ron Dermer, Israel's ambassador to the United States.
"Israel has no doubt that President-elect Trump is a true friend of Israel," Dermer said.
Trump pulled off the biggest upset in modern US political history through support from white working-class voters, defeating Hillary Clinton on November 8 in a number of states that had given Obama comfortable victories including Ohio, Pennsylvania and Wisconsin.
George Gigicos, the campaign's advance team director, told reporters that Trump would head to some of those states after the Thanksgiving holiday on November 24 in his first post-election trip outside the New York area and Washington.
"We're working on a victory tour now. It will happen in the next couple of weeks," he told reporters.
Transition officials said Trump would head Friday to his exclusive golf club in Bedminster, New Jersey.
The location would offer more seclusion and comes amid complaints by New Yorkers about the congestion in front of Trump Tower on bustling Fifth Avenue.
Trump has drawn the most post-election outrage by tapping anti-establishment firebrand Stephen Bannon, who pushes white identity politics, with House Democrats almost universally urging Trump to cancel his appointment as chief strategist.
But top House Democrat Nancy Pelosi, meeting in Washington with Vice President-elect Mike Pence, said her party stood ready to work with Trump on areas of potential agreement such as improving child-care access -- an issue the tycoon embraced during the campaign.
Pelosi, 76, a liberal from San Francisco who as House speaker was the highest-ranking woman in US history, has led House Democrats since 2002 with strong internal support.
But 43-year-old Congressman Tim Ryan from industrial Ohio on Thursday announced he would challenge Pelosi, saying the election defeat showed that Democrats need to change.
"Keeping our leadership team completely unchanged will simply lead to more disappointment in future elections," Ryan said in a statement.