London/Washington | Boris Johnson risked escalating a European trade war with Donald Trump this week by vowing to push ahead with a British digital sales tax, hours after the US administration threatened to punish France for imposing a similar measure.

The UK prime minister’s comments came ahead of a NATO summit that he was scheduled to attend late on Wednesday (AEDT) with his American counterpart near London as tensions rose over new European tech levies. Mr Trump has claimed they unfairly discriminate against US companies such as Google, Apple and Facebook.