Barack and Michelle Obama have been seen out for the first time since Donald Trump's controversial wire-tapping claims made international headlines.

The two smiled for the cameras as the exited the National Gallery of Art in Washington on Sunday, seeming at ease amid the row over whether the former President abused his powers to enact a "Watergate-level scandal" in a bid to topple Trump.

Donald Trump is yet to offer any evidence of whether the wire-tapping took place, and Obama's intelligence chief has denied any such activity took place.