In the closing weeks of the presidential campaign, President Donald Trump began telling his supporters that if former vice-president Joe Biden was elected, market mayhem would follow.

Washington | After weeks of delay, uncertainty and lawsuits, President-elect Joe Biden's team plunged into a formal transition, with Biden aides beginning to meet agency officials in preparation for a head-snapping Trump-to-Biden shift throughout the vast federal bureaucracy.

Following Monday night's long-postponed decision by a key administration official to approve the transition, Biden aides held at least 20 meetings with Trump officials and were in active discussions with every federal agency, as well as the White House, preparing for the daunting task of taking over a crumbling economy and overseeing the distribution of a coronavirus vaccine.

Donald Trump will reportedly pardon his former national security adviser who pleaded guilty to lying to the FBI during its investigation into Russian meddling in the 2016 presidential election.

The lawyer, Sidney Powell, has appeared alongside lawyers for Trump, including Rudy Giuliani, who are pressing their unfounded case that widespread voting fraud cost Trump the presidential election.

Donald Trump signed off on Tuesday (Wednesday AEDT) on giving Joe Biden the United States' most classified intelligence, the latest sign the President is accepting the transition of power even as he vows to fight the election result.

But Trump's refusal to concede the presidential race complicated Biden's ability to receive the more sensitive presidential briefing before the office in charge of the transition process formally acknowledged Biden as the apparent winner on Monday.

Joe Biden says government agencies have been "sincere" in reaching out to his team since the formal transition process began, including on the topics of national security and the coronavirus pandemic.

"Immediately, we've gotten outreach from the national security shop to just across the board and they're already working out my ability to get presidential daily briefs," Biden told NBC News on Tuesday (Wednesday AEDT).

More than three weeks after election day, General Services Administrator Emily Murphy on Monday acknowledged Biden as the apparent winner and set in train the transition process.

Donald Trump said his team would not block the process, although he is still trying to overturn the election result.

Pennsylvania's certification of its election results drew most of the attention on Tuesday (Wednesday AEDT), but three other states also returned official results.

Pennsylvania's 20 electoral college votes put Joe Biden's victory beyond doubt, but the certification of other states' results underscored his overall victory and moves the election process closer to its conclusion.

Madison, Wisconsin | Republicans filed a lawsuit on Tuesday (Wednesday AEDT) asking the Wisconsin Supreme Court to block certification of the presidential election results, even as a recount over Joe Biden's win over Donald Trump is under way.

Joe Biden says he is willing to meet Donald Trump, as the Democrat prepares to succeed the Republican in the White House.

When a reporter yelled out to Biden as he climbed into his motorcade asking if he will meet Trump, the President-elect replied: "Of course I would, if he asked."

Trump has refused to concede the election to Biden and has repeatedly claimed without evidence that it was stolen from him by a campaign of massive voter fraud

Trump grudgingly accepted on Monday (Tuesday AEDT) that the formal transition process could start, more than two weeks after Biden declared victory