Fired FBI chief James Comey has confirmed that Donald Trump urged him to drop a probe into former national security advisor Michael Flynn, in a preview of hotly awaited testimony Thursday that could rock the foundations of the presidency.

Vice President Mike Pence on Wednesday hailed 12 new NASA astronauts as "the best of us," after they were selected from a record-breaking pool of more than 18,000 applicants.

Fired FBI director James Comey confirmed in a statement Wednesday that US President Donald Trump urged him to drop an investigation into his former national security advisor Michael Flynn, then under scrutiny for his Russia contacts.

President Donald Trump announced Wednesday that he is tapping former Justice Department official Christopher Wray to serve as his new FBI director, on the eve of critical testimony by his ousted predecessor.

Activists detained while investigating working conditions at a Chinese factory making Ivanka Trump-branded shoes could face up to two years in jail, Amnesty International said Wednesday.

Top US intelligence officials will be grilled by lawmakers Wednesday about Russia's election interference and possible coordination with Donald Trump's campaign, ahead of a highly-anticipated appearance by sacked FBI director James Comey.

FBI experts visited Qatar in late May to analyze an alleged cyber breach that saw the hackers place the fake story with Qatar's state news agency, the US broadcaster said.

The Supreme Electoral Tribunal (TSE) held the first of four scheduled sessions to decide whether the 2014 reelection of president Dilma Rousseff and her then-vice president Temer should be invalidated because of corrupt campaign funding.

Trump, a ratings-obsessed former reality TV star, may not appreciate the worldwide attention paid to Comey's public testimony, being touted as the Super Bowl of high political drama.

US President Donald Trump threw his weight behind efforts to isolate Qatar on Tuesday, backing Saudi Arabia and its allies after they cut ties with Doha over claims it supports extremism.

Donald Trump will not use presidential powers to prevent the ex-FBI director James Comey from testifying to Congress Thursday, the White House said, setting the stage for potentially explosive testimony later this week.

US President Donald Trump has told his top diplomat to ignore trouble in Washington and re-engage with Russia to rebuild ties, Secretary of State Rex Tillerson said Tuesday.