US President Donald Trump said that US companies can again sell products to Chinese technology giant Huawei after an effective ban in May.

Trump clarified his comments earlier in the press conference, saying after his meeting with Chinese leader Xi Jinping he would allow Huawei to once again buy US products.

"US companies can sell their equipment to Huawei... there's no great, national emergency problem," Trump told reporters.

The US Commerce Department formally added Huawei to the list of companies the US government considers to be undermining America's interests in May.

Experts said that Huawei would be crippled by the effective ban, which would stop them buying advanced US chips over security concerns.