G7 summit has seen surprising progress – but the alliance is in peril like never before

They came battered and worn by battles back home for a few days by the sea, seeking sanctuary and solace in a wellness resort turned summit venue.

The G7 leaders will leave fortified by some surprisingly robust diplomatic progress but potentially terminal doubts remain for the alliance.

They have sent Russia a clear message. They may individually be on borrowed time as leaders but the West has Ukraine's back for as long as it takes.

And China's been on the sharp end of some particularly proactive diplomacy too.

Two signature deals will send billions more aid to Ukraine. The allies overcame stark differences between themselves to forge a creative agreement that uses interest from frozen Russian banking assets to usher $50 billion more dollars to Kyiv by the year's end.

In Moscow, the Russians did not conceal their fury at the prospect of their own money being used against them.

A 10-year bilateral security pact between America and Ukraine is another blow to Vladimir Putin.

He started this war to deter the expansion of the western military alliance - yet again, it is having the opposite effect.

The pact is a bridge to Ukraine joining NATO, even if that is still many, many years away.

G7's message to China

The G7 warned China in several ways. The final communique criticised its belligerence in the South China Sea and admonished Beijing for quietly helping Putin's war effort by trading dual-use products.

And the composition of this summit was also a message for Beijing. Pretty much the entire G20 was invited - except for China.

If you want to be in the club, they were not very subtly saying, then stop conniving with Putin and play by our rules.

In Beijing, that will be infuriating.

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The leaders have seemed all the better for their spell in the sunshine, spirits lifted before going home to face the music.

But what they can't do is dispel doubts about their future and that of the alliance.

Security pacts tend to survive changes of administration, and Ukraine will have its $50bn by the end of the year.

But what will the G7 look like when they next meet 12 months from now?

Trump threat looming

Donald Trump looks increasingly likely to win the US election and Joe Biden's performance here will have done nothing to reassure allies. He has seemed vacant and distracted at times - older than ever.

Trump has no time for multilateral organisations. This was made abundantly clear in his first term in office when, in his transactional zero-sum game world view, they make no sense.

This time next year, Trump could be six months into destroying NATO, deserting Ukraine and dismantling the G7.

When he was president first time around - for all his puerile antics - Trump could do limited damage at these summits, contained by the likes of Merkel and Macron, who were both at the height of their powers.

Olaf Scholz is no Merkel and may be gone by then, joining Rishi Sunak, Japan's Fumio Kishida and Canada's Justin Trudeau as leaders perhaps too heading for the history books.

And Macron is on the way to becoming a lame duck president hamstrung by a far-right national assembly if current polling is correct.

The alliance is in peril like never before, however successful they have been holding it together for now.