Barack Obama issues thinly veiled attack on Donald Trump: 'We can't hide behind a wall'

Barack Obama has issued a thinly veiled attack on Donald Trump, saying the US should not hide “behind a wall".

While sharing a stage with Angela Merkel at an event in Berlin to mark the 500th anniversary of the Reformation, the former president said the German Chancellor was one of his “favourite partners” during his presidency.

During a wide-ranging address, Mr Obama discussed the issue of foreign aid in the developing world, which Mr Trump has suggested he could heavily reduce as part of his ‘America First’ stance.

Mr Obama said: "If there are disruptions in these countries, if there is bad governance, if there is war or if there is poverty, in this new world that we live in we can't isolate ourselves.

"We can't hide behind a wall."

One of Mr Trump's most prominent campaign promises was to build a wall on the US border with Mexico to keep immigrants out, although no money was included for the controversial scheme in the President's recent budget.

Ms Merkel met Mr Obama before Mr Trump, who is also in Europe for the Nato summit, despite him not being a serving politician.

The speaking invitation to Mr Obama was made long before Mr Trump was elected. Commentators have said her decision to do so reflects her preference for Mr Obama, with whom she is known to be friendly.

In contrast, when Ms Merkel met with Mr Trump at the White House earlier this year, the pair's relationship appeared frosty, with the US president apparently refusing to shake hands with the German leader for photographers.

On Thursday’s meeting, the Chancellor and Mr Obama spoke on a range of political and foreign policy issues.

"The world is at a crossroads," said Obama, speaking in front of the Brandenburg Gate.

The widening inequality gap within nations as well as between nations was a major concern, he said. At the same time, he said, "the world has never been wealthier, more healthy and never been better educated."

"If we can sustain that progress, then I'm very optimistic about our future. My job now is to help them take it to the next step," he added.

Mr Obama also paid tribute to the victims of the Manchester bombing, in which 22 people died.

“At a time, when the world is a very complicated place, when we can see the terrible violence that took place just recently in Manchester," he said.

He continued: “We had a moment back stage to send a message to the people of Manchester and tell them how heartbroken we are, about the loss of life and to grieve with the families."