WASHINGTON -  President Donald Trump vowed Saturday to improve floundering ties with Russia, while also reassuring close US allies he supports Nato. Trump faced a first legal defeat amid growing international alarm over his halt to refugees and travelers from certain Muslim majority countries, with a federal judge blocking part of the ban.

The temporary stay orders authorities to stop deporting dozens of refugees and other travelers who had been detained at US airports since Trump signed his measure Friday afternoon. British Prime Minister Theresa May indicated she does "not agree" with the restrictions, and will intervene if they affect UK nationals.

French President Francois Hollande warned of the "economic and political consequences" of the American leader's protectionist stance. Trump's sweeping executive order suspends the arrival of refugees for at least 120 days and bars visas for travelers from seven Muslim majority countries for the next three months. The move sparked large protests at major airports across the country. At New York's John F. Kennedy International Airport, some of the 2,000 demonstrators chanted "Let them in, let them in!"

Trump's friendly stance toward Putin, whom France and Germany accuse of seeking to undermine Western unity, is being scrutinized since he won the US election in November. The White House hailed the call with Putin as a "significant start" to better US-Russia ties, while the Kremlin said the pair agreed to develop relations "as equals" and to establish "real coordination" against the Islamic State group.

Trump took office last week with US-Russia relations at new Cold War-level lows amid accusations by American intelligence agencies that the Kremlin hacked Democratic Party emails as part of a pro-Trump campaign to influence November's election. The president -- who has raised the prospect of easing sanctions imposed against Russia after its annexation of Ukraine's Crimean Peninsula in 2014 -- has cast doubt on whether Russia meddled in the election.

In a flurry of calls that began early in the morning and rounded out an already frantically paced week, Trump spoke with Japanese Prime Minister Shinzo Abe, German Chancellor Angela Merkel, Putin, Hollande and Australian Prime Minister Malcolm Turnbull. The conversations gave the US president an early opportunity to explain new policies that have baffled and unnerved much of the rest of the world -- particularly his order to temporarily halt all refugee arrivals and those of travelers from Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen.

European leaders are also concerned about Trump's virulent criticism of Nato -- he has dubbed the transatlantic military alliance "obsolete" -- at a time when it stands as the main defense against Putin. But in his call with Merkel, Trump agreed on Nato's "fundamental importance," the White House said. The United States provides significant funding to Nato, and Trump has urged other member nations to step up their contributions.