Taormina, Italy: G7 leaders meet on Friday is determined to put on a display of united resolve in the fight against jihadist terrorism, despite deep divisions on trade and global warming.
The two-day summit in Sicily's ancient hilltop resort of Taormina kicks off four days after children 22 people were killed in a concert bomb attack in Manchester.
British Prime Minister Theresa May will lead a discussion on terrorism in one of Friday's working sessions and is expected to issue a call for G7 countries to put more pressure on internet companies to remove extremist content.
"The fight is moving from the battlefield to the internet", a senior British official said ahead of the talks.
With May and Donald Trump among four new faces in the club of the world's major democracies, the gathering in Italy is being billed as a key test of how serious the new US administration is about implementing its radical policy agenda, particularly on climate change.
Senior officials are preparing to work through the night of Friday and Saturday in a bid to bridge what appear to be irreconcilable differences over Trump's declared intention of ditching the US commitment to the landmark Paris according on curbing carbon emissions.
Officials acknowledge the summit, one of the shortest in the body's history, is effectively about damage limitation against a backdrop of fears among US partners that the Trump presidency, with its 'America First' rhetoric, could undermine the architecture of the post-World War II world.
Summit host Paolo Gentiloni, a caretaker Italian prime minister also making his G7 debut, acknowledged as much on the eve of the meeting.
"It won't be an easy discussion", he said. "The Italian presidency will try to ensure it is a useful one, capable of bringing the different positions closer together".
The build-up to the summit has seen even the terrorism issue, normally a unifying subject, sow division with Britain enraged that intelligence it shared with the United States in relation to the Manchester attack, including pictures of the bomb, was leaked to the New York Times and other US media.
Seeking to defuse the row, Trump pledged on Thursday to prosecute those responsible for the leaks and described the relationship with Britain as "cherished".
For Trump, who touched down at a US military airbase near the summit venue late Thursday, the talks will be the final leg of his first presidential foray overseas.
The gruelling week-long trip has temporarily diverted attention from domestic concerns focused on alleged campaign collusion with Russia.
It has also enabled Trump to position himself as a more statesmanlike figure and, notably after his meeting with Pope Francis, as a man of peace stances which European officials hope will edge him towards compromise with partners across a broad range of issues.
Updated Date: May 26, 2017 10:44 AM