The British government privately told the Chinese technology giant Huawei that it was being banned from Britain's 5G telecoms network partly for "geopolitical" reasons following huge pressure from President Donald Trump, the Observer has learned.

Huawei was told that geopolitics had played a part, and was given the impression that it was possible the decision could be revisited in future, perhaps if Trump failed to win a second term and the anti-China stance in Washington eased.