Boris Johnson has spoken to Donald Trump about 5G mobile networks, trade and global security in a phone call, the White House said.
It was the second call in the space of a week between the two world leaders after their conversation on July 26, and comes ahead of them meeting later this month at the G7 economic summit in France.
Mr Trump effectively banned Chinese firm Huawei from trading with US companies without approval in May over concerns about the security of its 5G equipment and alleged links to the Chinese government, although he subsequently eased some of the restrictions.
The UK Government then postponed a decision on whether or how to involve Huawei in infrastructure for the next generation of mobile technology in the UK.
In one of the final acts of Theresa May's administration, former culture secretary Jeremy Wright said the Government is "not yet in a position" to decide and is still seeking clarity on the implications of US action against it.
A White House spokesman said: "President Donald J Trump spoke with Prime Minister Boris Johnson yesterday to discuss areas of further co-operation, especially relating to trade, 5G and global security.
"The president reiterated his strong appreciation for the special relationship between the United States and United Kingdom and noted he is looking forward to meeting with the Prime Minister at the G7 summit in Biarritz, France, later this month."
The president has repeatedly praised the new prime minister, claiming people call Mr Johnson "Britain Trump" because of their similar styles.
Additional reporting by Press Association
