US president-elect Joe Biden has said the Trump administration’s refusal to give his team access to key federal agencies is affecting their ability to create a plan to respond to the coronavirus pandemic, particularly around vaccine distribution.

Speaking in Wilmington, Delaware, Mr Biden referenced the refusal by the General Services Administration to name him the apparent winner of the election.

The refusal has blocked Mr Biden’s team from receiving federal funds allocated for the transition and barred his team from meeting with their counterparts to collect relevant information.

Mr Biden said that his transition team does not have “all the information that we need to get from all the various agencies,” and that, as a result, “we’re not able to deal with everything from testing to guidance to the all-important issue of vaccine distribution”.

Mr Biden has launched his own working group focused on crafting an actionable plan to rein in the pandemic. But he and his aides have said a lack of access to the current planning in the federal government will make the response much more difficult when he does take office in January.

Earlier, Mr Biden told state governors he would help them access the resources they need to overcome coronavirus, warning Donald Trump’s attempt to block the transition of power has hindered the flow of information about programmes to fast-track a vaccine.

Speaking during a video conference with the National Governors Association’s leadership team, which includes five Republicans and four Democrats, Mr Biden said: “Unfortunately, my administration hasn’t been able to get everything we need.”

He specifically cited Operation Warp Speed, the federal government’s partnership with private pharmaceutical companies to develop a Covid-19 vaccine.

Mr Biden participated from a theatre in Wilmington, Delaware, with vice president-elect Kamala Harris. Also appearing online were the leaders of Mr Biden’s virus task force: Vivek Murthy, a former surgeon general; David Kessler, an ex-head of the Food and Drug Administration; and Marcella Nunez-Smith of Yale University.

Among the Democratic governors participating was Gretchen Whitmer of Michigan, which has been among those Mr Trump has targeted for unfounded claims of fraud.

“I want you to know that I will be your partner in the White House,” Mr Biden told the governors, including Republicans Larry Hogan of Maryland, Asa Hutchinson of Arkansas, Kay Ivey of Alabama, Charlie Baker of Massachusetts and Gary Herbert of Utah.

Mr Biden promised state leaders that he would “make sure you get the resources you need… to beat this virus”.

Mr Hogan told The Associated Press recently that Mr Trump’s wild and unsupported claims of widespread voter fraud were “dangerous” and “embarrassing”.

Mr Hutchison said over the weekend that Mr Biden would be the next president, and called on the Trump administration to give him access to the intelligence briefings he needs in order to be fully prepared to lead the country on January 20, Inauguration Day.

Meanwhile two Republican senators are criticising Mr Trump and his team for their efforts to pressure state and local election officials to overturn Mr Biden’s victories in several closely contested states.

Senator Mitt Romney, one of the president’s most vocal GOP critics, tweeted on Thursday:“It is difficult to imagine a worse, more undemocratic action by a sitting American President.”

He also criticised Mr Trump for resorting to “overt pressure on state and local officials to subvert the will of the people and overturn the election.”

Senator Ben Sasse went after Mr Trump’s lawyer Rudy Giuliani, who held a press conference on Thursday presenting a list of far-fetched, thoroughly debunked claims on the 2020 election.

Mr Sasse tweeted: “Rudy and his buddies should not pressure electors to ignore their certification obligations under the statute. We are a nation of laws, not tweets.”