Foreign ministers from the Group of Seven major industrialized nations meet on Monday for an annual gathering, with Europe and Japan seeking clarity from the United States on an array of issues, especially Syria.
The two-day summit in Tuscany comes as the United States moves a Navy strike group near the Korean peninsular amid concerns over North Korea's nuclear ambitions, and as the West's relations with Russia struggle to overcome years of mistrust.
But the civil war in Syria is likely to dominate talks, with Italy hoping for a final communique that will reinforce United Nations' efforts to end six years of conflict.
The meeting will give Italy, Germany, France, Britain, Canada and Japan their first chance to grill the new U.S. Secretary of State Rex Tillerson on whether Washington is now committed to overthrowing Syrian President Bashar al Assad.
President Donald Trump had hinted he would be less interventionist than his predecessors and more willing to turn a blind eye to human rights abuses if it was in U.S. interests.
Given this, the U.S. attack on Syria last week in retaliation for what it said was a chemical weapons attack by Assad's forces on Syrian civilians confounded many diplomats.
However, there is uncertainty over whether Washington now wants Assad out, as many Europeans are pushing for, or whether the missile strikes were simply a warning shot.
The U.S. Ambassador to the United Nations Nikki Haley said at the weekend that regime change in Syria was a priority for Trump, while Tillerson said on Saturday the first priority was the defeat of Islamic State.
The mixed messages have confused and frustrated European allies, who are eager for full U.S. support for a political solution based on a transfer of power in Damascus.
"The Americans say they agree, but there's nothing to show for it behind (the scenes). They are absent from this and are navigating aimlessly in the dark," said a senior European diplomat, who declined to be named.
The foreign ministers' discussions will prepare the way for a leaders' summit in Sicily at the end of May.
Efforts to reach an agreement on statements and strategy ahead of time - a normal part of pre-meeting G7 diplomacy - has gone very slowly, partly because of a difficult transition at the U.S. state department, where many key positions remain unfilled.
Some issues, such as trade and climate change, are likely to be ducked in Tuscany. "The more complicated subjects will be left to the leaders," said an Italian diplomat, who declined to be named because he was not authorized to speak to the press.
However, the foreign ministers will talk about Libya.
Italy is hoping for vocal support for a United Nations-backed government in Tripoli, that has struggled to exert its influence in the city, let alone in the rest of the violence-plagued north African country.
The Trump administration has not yet defined a clear policy and Rome fears Washington may fall into step with Egypt, which supports general Khalifa Haftar, who operates in eastern Libya.
The struggle against terrorism, relations with Iran and on-going instability in Ukraine will also come up for discussion, with talks due to kick off at 4.30 p.m. (1430 GMT).