The European Union has warned that its trade with the United States could be effectively wiped out if Washington makes good on its threat to slap a 30% tariff on goods imported from the bloc.

The EU says the U.S. is resisting efforts to strike a trade deal and warned of countermeasures if no agreement is reached with U.S. by Aug. 1.

U.S. President Donald Trump said he believed Britain would fight to defend the United States but suggested he could not say the same for the European Union, a factor in his decision not to sign a trade deal with the bloc.