Speaking on German television Merkel also expressed regret about President Donald Trump's surprise decision to withdraw his endorsement of the recent G7 summit's final communique.

German Chancellor, Angela Merkel says, "I worked hard for a compromise, we struggled with it for a long time ... and then afterwards the withdrawal, so to speak, via tweet, is of course sobering and a bit depressing."

Despite tensions over Trump's intended trade tariffs the US and its G7 allies had put on an apparent show of unity at the end of the tense summit.

But within minutes of the official summit communiqué, Trump lashed out at Canadian Prime Minister Justin Trudeau accusing him of making “false statements" during the closing news conference.

Asked about Trump’s tweets and the future of the G7 Trudeau refused to respond directly but later issued his own tweet saying "We are focused on everything we accomplished here at the G7 summit."