Theresa May tells Trump of Britain's 'deep concern'

British Prime Minister Theresa May has spoken with President Donald Trump and expressed "deep concern" about his threatened trade war with the European Union.

May's office says she discussed the issue with Trump during a telephone call Sunday.

Trump has threatened to tax European cars if the EU boosts tariffs on American products in response to the president's plan to increase duties on steel and aluminum.

May's office says she "raised our deep concern at the president's forthcoming announcement on steel and aluminum tariffs, noting that multilateral action was the only way to resolve the problem of global overcapacity."

The leaders also discussed Syria and humanitarian concerns in Eastern Ghouta. May's office says they agreed "the overwhelming responsibility" for suffering falls on the Syrian government and Russia, its main backer.