A U.S. flag is seen on a bicycle taxi, in Havana, Cuba April 17, 2019. REUTERS/Fernando Medina

LONDON (Reuters) - Britain said it was concerned by new attempts by the United States to require foreign companies to abide by U.S. sanctions on Cuba that have been rejected by Britain and other European countries.

“The extraterritorial application of ... sanctions, which we consider to be illegal under international law, threaten to harm UK and EU companies doing legitimate business in Cuba by exposing them to liability in U.S. courts,” Britain’s foreign office said in a statement on Thursday.

“We will work alongside the EU to protect the interests of our companies,” the statement added.

On Wednesday, Washington imposed new sanctions and other punitive measures on Cuba and Venezuela, seeking to ratchet up pressure on Havana to end its support for Venezuela’s socialist president, Nicolas Maduro.