WASHINGTON >> The fun and flattery are largely over for President Donald Trump as he embarks on his third overseas trip in a month, this time facing a flurry of international crises, tense negotiations and a growing global to-do list.

Trump heads first to Osaka, Japan, for the annual Group of 20 summit, then on to South Korea for consultations on North Korea’s nuclear program. The agenda for his four-day trip is as laden with hazards for the president as it is light on the ceremonial pomp that marked his recent state visits to Japan and the United Kingdom.

The showdown between the U.S. and Iran, a trade war with China and the threat of fresh election interference by Russia are just some of the issues confronting the American leader who has shown little patience for the subtleties of global interactions and whose administration has struggled to grapple with simultaneous challenges.

The president will meet one-on-one with at least eight world leaders on the summit’s sidelines as he faces mounting pressures to deliver results on a lengthy roster of global concerns. But White House officials are playing down prospects of specific accomplishments in what will almost certainly be Trump’s most consequential trip of the year.

Trump said before departing today that he’d be meeting “competitors” from other nations, adding, “That’s OK. We’re doing great. We’re doing better than any of them.”

His calendar includes sit-downs with Russian President Vladimir Putin, Chinese President Xi Jinping, Turkey’s Recep Teyyip Erdogan and Saudi Crown Prince Mohammed bin Salman, all of whom have authoritarian tendencies, as well as disquieted allies including Germany’s Angela Merkel and more contented ones such as Japanese Prime Minister Shinzo Abe.

The president left Washington days after pulling back from the brink of armed conflict with Iran and as he trades threats over its nuclear program and support for terror groups. With Iran threatening to breach uranium enrichment limits set in the 2015 nuclear accord as soon as Thursday, Trump will be asked to articulate his strategy for containing Iran to skeptical world leaders after pulling the U.S. from the deal last year.

“The leaders are going to be pressing the president for clarity and then to get into a unified allied approach to the challenge, and it’s just simply unclear to me whether we have that policy or that approach,” said Heather Conley, director of the Center for Strategic and International Studies’ Europe program.

Trump will also find himself face-to-face with Putin for the first time since special counsel Robert Mueller’s investigation ended without finding evidence that the Trump campaign criminally conspired with Russia during the 2016 election. It will also be their first meeting since their summit in Helsinki in July 2018, when Trump declined to side with U.S. intelligence agencies over Putin on the question of election interference, leading to an uproar at home and abroad.

Trump told reporters as he left the White House that he expects a “very good conversation” with Putin but added that “what I say to him is none of your business.”

White House officials said Trump would warn Putin to refrain from interfering in U.S. elections, though Trump has been criticized for joining with Putin in attacking Mueller’s probe, and advisers worry he may do so once again.

Last November, Trump canceled a planned meeting with Putin at the G-20 in Argentina after Russia seized two Ukrainian vessels and their crew in the Sea of Azov, but the continued detention of the crew members does not appear to be deterring the leaders from meeting this time. Aside from Iran, the leaders are expected to discuss hotspots in Syria and Venezuela, as well as nuclear weapons.

With Xi, a senior administration official said, Trump’s top aim will be rebooting trade negotiations between the two countries after they collapsed earlier this year. In an interview with Fox Business Network on Wednesday, Trump threatened again to impose even stiffer tariffs on Chinese imports to the U.S. if talks remain stalemated. But officials in both nations are looking for an off-ramp as concerns mount about the economic impact of the yearlong trade war.

Trump’s meeting with Erdogan will be his first since announcing, and then backing off, a withdrawal of U.S. forces from Syria. There also is a growing rift between the two NATO allies over Turkey’s planned purchase of a Russian surface-to-air missile system and a U.S. threat to suspend planned deliveries to Turkey of the F-35 Joint Strike Fighter.

Trump will also meet with Crown Prince Mohammed, who U.S. intelligence services concluded ordered the grisly killing of Washington Post columnist Jamal Khashoggi, a U.S. resident. Trump has long been loath to scold authoritarian leaders for human rights abuses. He has continued to pursue a close relationship with Saudi Arabia, a lynchpin to the U.S.’ Middle East strategy to counter Iran, despite its role in furthering humanitarian disaster in Yemen’s civil war.

White House officials said there are no plans for a meeting in South Korea between Trump and North Korea’s Kim Jong Un, with whom the president has restarted diplomacy-by-correspondence since their failed Hanoi summit in March. But Trump is to speak with South Korean President Moon Jae-in about efforts to bring North Korea back to the negotiating table as the American holds out hope for an elusive legacy-making nuclear deal. Moon told the Associated Press and other news agencies Wednesday that the U.S. and North Korea are holding “behind-the-scenes talks” to arrange a third summit between the two leaders.

Never fully willing to pass up domestic politics, even when overseas, Trump will have to divide his attention between affairs of state and his reelection effort as Democrats are set to face off today and Thursday in their first debates in the process to select their nominee to challenge him next fall.

Trump said he planned to watch the “boring” first matchup tonight, which will air as he is aboard Air Force One. But he will be in meetings with world leaders when Democratic front-runner Joe Biden and others take the stage on the second night. Trump aides believe the scheduling fluke will highlight the signature advantage of incumbency — that the president already occupies the job the Democrats want.