President-elect Joe Biden’s transition team is considering legal action over a federal agency’s delay in recognising the Democrat’s victory over US President Donald Trump in last week’s election, a Biden official said on Monday.

The General Services Administration (GSA) normally recognises a presidential candidate when it becomes clear who has won an election so that a transition of power can begin.

That has not yet happened despite US television and news networks declaring Biden the winner on Saturday after he secured enough electoral votes to secure the presidency.

The law does not clearly spell out when the GSA must act, but Biden transition officials say their victory is clear and a delay is not justified, even as Trump refuses to concede defeat.

Trump has repeatedly claimed, without evidence, that there was widespread voting fraud and has filed a raft of lawsuits to challenge the results.

Election officials across the country say there has been no evidence of significant fraud, and legal experts say Trump’s efforts are unlikely to succeed.

GSA Administrator Emily Murphy, appointed by Trump in 2017, has not yet determined that “a winner is clear,” a spokeswoman said. A source close to Murphy said she was a thorough professional who would take her time making a careful decision.

A Biden transition official told reporters on a call that it was time for the GSA’s administration to grant what is known as an ascertainment recognising the president-elect, and said the transition team would consider legal action if it was not granted.

“Legal action is certainly a possibility, but there are other options as well that we’re considering,” said the official, who spoke on condition of anonymity, declining to outline other options.

The delay is costing the Biden team access to millions of dollars in federal funding and the ability to meet with officials at intelligence agencies and other departments.

The transition team needs to be recognised to access funds for salaries, consultants and travel, as well as access to classified information, the official said.

In addition, the team has no access to the State Department, which usually facilitates calls between foreign leaders and the president-elect, the official said.

A senior administration official said the agency did not approve the start of a formal transition process in 2000 for five weeks while Republican George W Bush and Democrat Al Gore battled over an election that came down to just hundreds of votes in Florida.