By Steve Holland and Alexandra Alper

WASHINGTON (Reuters) - Under mounting pressure to take action against the spread of the coronavirus, President Donald Trump on Wednesday suspended travel from Europe to the United States, except for the UK, for 30 days starting on Friday.

The president, who faces re-election in November, took the dramatic step in a somber Oval Office speech as he battles to address the health and economic shocks to Americans from the sometimes fatal virus and responds to criticism that he has not taken the coronavirus threat seriously enough.

“We are marshalling the full power of the federal government and the private sector to protect the American people," he said.

"This is the most aggressive and comprehensive effort to confront a foreign virus in modern history," he said.

Trump, whose re-election bid on Nov. 3 could hinge on how well he responds to the crisis, stopped short of declaring a national emergency.

But he pulled no punches in saying Europe was partly to blame for the virus' spread in the United States, where it has killed at least 37 people and infected 1,281. His travel restrictions on Europe were similar to what he declared on travel from China when the illness was spreading wildly there.

“The European Union failed to take the same precautions and restrict travel from China and other hot spots. As a result, a large number of new clusters in the United States were seeded by travelers from Europe," he said.

As the U.S. stock market took another hit from the virus on Wednesday, Trump said he would take emergency action to provide financial relief for workers who are ill, quarantined or caring for others due to the illness.

He said he was instructing the Treasury Department to defer tax payments without interest or penalties for certain businesses and individuals affected.

Trump added he was also instructing the Small Business Administration to provide capital and liquidity to firms affected by the virus.