Air Force One touched down in Warsaw late Wednesday, for what is the US president's second foreign outing after a European tour in May .
Donald Trump's high-stakes trip to Europe, where he faces a prickly G20 meeting and animosity from traditional US allies, kicks off on a comforting note Thursday -- in front of a friendly crowd bussed in by his sympathetic Polish hosts.
Air Force One touched down in Warsaw late Wednesday, for what is the US president's second foreign outing after a European tour in May that exposed fierce mistrust.
The US president's four-day swing starts in Warsaw, where he will deliver a major speech, before moving on to the northern German city of Hamburg for his first G20 summit, where tricky geopolitical currents -- from rumbling transatlantic discord to increasingly difficult ties with China -- will converge.
Looming large over the entire visit is Pyongyang's test of an intercontinental ballistic missile that could deliver a nuclear payload to Alaska.
Tough-talking Trump had previously vowed North Korea would not be allowed to possess an ICBM, and leaders from rival and allied powers alike will be watching closely to see whether his threats were bluster or will crystallise into action.
After repeatedly urging Beijing to ratchet up the pressure on North Korea, Trump will hold what promises to be a testy meeting with Chinese President Xi Jinping in Hamburg to trace the next steps.
"Trade between China and North Korea grew almost 40% in the first quarter. So much for China working with us - but we had to give it a try!" Trump tweeted indignantly on Wednesday.
On Friday, Trump will hold a meeting with Russian President Vladimir Putin that will -- amongst other things -- be pored over for its significance to US domestic politics.