President Donald Trump’s national security adviser Robert O'Brien pledges a very professional transition from the National Security Council to Joe Biden. (Photo: AFP)

Robert O'Brien said on Monday that Trump might still win a second term if the courts determine that there was widespread voter fraud.

The General Services Administration has not yet signed the paperwork recognizing Biden as the election winner and allowing his transition team to begin its work, which includes accessing classified information. A vote recount is taking place in Georgia and another is likely to happen in Wisconsin.

The Trump administration is pushing legal campaigns to attempt to prove voter fraud in several states.