Boris Johnson has given the US a de facto veto over whether to allow Huawei to build Britain’s 5G network.

Mr Johnson said that the “key criterion” in ruling on the Chinese company would be whether it would prejudice co-operation with other “Five Eyes” security partners.

The US has warned repeatedly that it would reduce co-operation with any state that chose Huawei. Mr Johnson, however, has rejected President Trump’s demand that Britain, along with other European countries, take back jihadists who went to Syria and were detained by US forces after the fall of Islamic State.

The decision on whether to allow Huawei to build part of Britain’s 5G network has been postponed until after the election. Mr Trump said that he had received assurances