Pelosi blasts White House 'cover up' of Ukraine call

The White House engaged in a "cover up" by suppressing a record of President Donald Trump's phone call to Ukraine, now at the centre of an abuse of power complaint, top Democrat Nancy Pelosi charged Thursday.

"This is a cover up," the speaker of the House of Representatives told reporters, as she laid out part of her case for impeaching the US president.

A whistleblower alleged White House lawyers ordered the record of the call be moved to a separate restricted electronic system, which Pelosi said "the White House used to hide information of a political nature.