Theresa May has said the G7 summit where leaders clashed repeatedly with Donald Trump was “difficult”, but the UK intended to fully honour its commitment to the joint statement that the US has since disavowed.

Speaking in the House of Commons, the prime minister said Britain would abide by the final communique signed by leaders in Quebec, which was dramatically abandoned by the president after the summit.

“This was a difficult summit, with at times some very candid discussions,” May told MPs. “But the conclusion I draw is that it is only through continued dialogue that we can find ways to work together to resolve the challenges we face.



“The countries round the G7 table have been pillars of the rules-based international order, which has benefited all our citizens and, I believe, the world as a whole. The United Kingdom, with our allies and partners, will continue to play our part in promoting that order to the benefit of all.”

Trump disowned the agreement hours after leaving the gathering, launching a personal attack on the Canadian prime minister and accusing other countries of “robbing” the US.

Speaking in the House of Commons, the Labour leader, Jeremy Corbyn, said the White House was “inhabited by a president committed to his slogan – America first”, who was set on dismantling multilateral agreements.

Angela Merkel described Trump’s behaviour as “sobering and slightly depressing”, and suggested international leaders should be more polite to each other.

“The situation is not pleasant,” the chancellor told German television in a rare and lengthy interview. “I don’t think that taking the rhetoric up a few notches is going to make things much better.”

World leaders at the summit believed they had a deal until the US president pulled out of the previously agreed communique, which represented a minimal show of unity with deep disagreements between Trump and the other leaders about trade.

Frustrations had been mounting over Trump’s decision to withdraw from the Iran nuclear deal and the Paris climate agreement, and most recently to change the rules for trade tariffs on steel and aluminium.

The US nevertheless appeared to have agreed to a form of words on contentious issues after an all-night negotiating session by officials from all sides. US reporters travelling on Air Force One to south-east Asia only discovered when the plane landed at Crete to refuel that the president had changed his mind.

The communique said the leaders of the US, Canada, Britain, France, Italy, Germany and Japan agreed on the need for “free, fair and mutually beneficial trade”, and the importance of fighting protectionism. “We strive to reduce tariff barriers, non-tariff barriers and subsidies,” the statement said.

Like last year, the communique made it clear the US had a different view on climate change and how to tackle it from that of the other six countries, increasingly being referred to informally as the G6.

No 10 sources said although the prime minister did not have a bilateral meeting with Trump in Quebec, the pair had spoken “in the margins” of the summit about the president’s visit to Britain in July.

The trip will follow a Nato summit in Brussels, at which Trump is expected to increase pressure on other countries in the alliance to join the US and UK in committing at least 2% of GDP to defence spending.

Trump is believed to have his eye on Germany in particular. Merkel admitted he “has a point” over the comparatively low German defence budget, which is 1.1% of GDP and not due to reach 2% before 2030.

The German chancellor, who has been increasingly frank over her frustrations with Trump, did not hide her disappointment at having failed to persuade him to change his mind, particularly over trade tariffs.

“Sometimes, I have the impression that the US president believes that only one side wins while the other loses,” Merkel said, adding that she preferred to see situations as “win-win”.

Merkel said she would continue to engage with Trump in the hope of winning him round. She said the tensions that dominated the summit did not make her any less committed to the transatlantic relationship, but it was no longer something Germany could rely on.

The US president would not be allowed to have the upper hand, she said, particularly regarding the trade tariffs. The EU’s decision to impose retaliatory tariffs showed “[we] won’t let ourselves be repeatedly taken advantage of”.