"I think they won't say no to us as long as they go through those rigorous tests and look at it in a serious manner and I think if they do say no, it won't be to us."
On Monday Donald Trump's national security adviser, John Bolton, said British officials told him they were going "back to square one" on their assessment of whether to allow Huawei to build parts of UK 5G networks.
The founder and chief executive of Huawei has say he doesn't believe the UK will turn down a deal with the Chinese company.
In an interview with Sky News Ren Zhengfei said "the UK won't say no to us" when it comes to including Huawei in its critical infrastructure, adding that he thought Boris Johnson was a "very decisive" and a "very capable person".
Earlier this year The Daily Telegraph revealed that Theresa May had given the green light to Huawei to build parts of the 5G network, despite concerns over whether it poses a risk to national security.
The decision put the UK at odds with Washington, which has been upping pressure on its allies to bar Huawei amid claims its technology could be used for espionage by Beijing – something repeatedly denied by the Chinese company.
The US previously warned that it would withhold intelligence from Britain if Huawei's technology was used in its network, and signs emerged overnight that Washington was taking a firmer stance on the company.
Mr Ren described the UK's upcoming decision as "very important".
He said: "I noticed the third day that [Mr Johnson] was in office, he said UK should roll-out 5G as soon as possible.