Donald Trump’s negotiators have signalled that the next prime minister’s hopes of a post-Brexit trade deal with the United States rest on his willingness to fall in line with tough American policies against the Chinese telecoms giant Huawei.

Whitehall correspondence seen by The Sunday Telegraph reveals that British officials close to transatlantic trade talks believe allowing Huawei to ­provide equipment for new 5G mobile networks could be a deal-breaker.

In one message a civil servant lifts the lid on how the controversy over the alleged threat to security posed by Huawei is intertwined with a web of diplomatic and trade concerns in Washington DC.

A British refusal to back curbs on Huawei would be viewed, for instance, as “undermining Washington’s efforts to reinvigorate the World Trade Organisation [WTO]”, the official warns.

The comment refers to ongoing efforts by American diplomats to reform the special status of “developing” economies under WTO rules.

Mr Trump has insisted China should no longer qualify for such preferential treatment as part of his trade war with President Xi.