Donald Trump’s announcement of unprecedented new measures to tackle the coronavirus prompted shock and criticism from former officials and commentators on Wednesday evening.

In an address to the nation from the Oval Office that was marked by missteps, Mr Trump declared severe restrictions on travel between the US and Europe for 30 days — with the exception of the UK and Ireland.

The president, who has faced criticism for not moving fast enough to contain the public health crisis, described the measures as "the most aggressive and comprehensive effort to confront a foreign virus in modern history.”

Susan Rice, who played a key role in the Obama administration's response to the Ebola crisis in her role as national security advisor, was among the first to tweet her reaction, saying only: “OMG”.

One of Obama’s top foreign policy advisers, Ben Rhodes, described the president’s speech and his handling of the crisis as a “dystopian nightmare”.

“Republican leaders knew better. They knew this man was not at all up to this job, and yet they've supported him, defended him, literally voted to keep him in office despite that knowledge. And now here we are in this dystopian nightmare, without a mature adult to run the country,” he said.

The Democratic Party’s top leaders, House Speaker Nancy Pelosi and Senate Minority Leader Chuck Schumer, criticised the president for not taking action to stop the spread of the virus within US borders.

“We have a public health crisis in this country and the best way to keep the American people safe and ensure their economic security is for the president to focus on fighting the spread of the coronavirus itself. Alarmingly, the president did not say how the administration will address the lack of coronavirus testing kits throughout the United States,” they said in a joint statement.

Anthony Scaramucci, who briefly served as White House director of communications in the Trump administration, said that the president “looked like a scared, sedated puppy who just got neutered.”

Several parts of the speech and the measures announced prompted more questions than answers. The White House was forced to walk back a number of announcements in the address — including a part in which Mr Trump said that cargo would be included in the ban.

Amanda Sloat, senior fellow at Brookings, questioned why Britain was exempted from the travel ban.

“Trump’s ‘Europe but not Britain’ ban is illogical. UK has more coronavirus cases than some EU states — British Health Minister just tested positive. UK still has open borders with EU. Viruses don’t respect borders.”

Mr Trump did find support from his own party, however.

South Carolina Republican and key ally of the president, Lindsey Graham, said Mr Trump “laid out a very good roadmap to achieve economic stability and contain the spread of coronavirus. I hope Congress will work with him in a constructive fashion to achieve these goals.”

His son, Donald Trump Jr, also praised the speech.