The US Secretary of State has warned the British Government to be "vigilant and vocal against a host of Chinese activities that undermine the sovereignty of all nations".
Mike Pompeo made the comments following talks at Downing Street on Wednesday afternoon, reiterating Washington's concerns over proposals to use the Chinese tech giant Huawei to develop a 5G network.
Mr Pompeo said he and the prime minister had discussed the involvement of the firm at length, adding: "China peddles corrupt infrastructure deals in return for political influence.
"Its bribe-fuelled debt diplomacy undermines good governance and threatens to upend the free market model on which so many countries depend."
He hinted a wrong move from the UK could strike tensions in the trans-Atlantic special relationship, but stated he has "great confidence" such steps would not be taken by Westminster politicians.
He said: "With respect to 5G, we continue to have technical discussions. We are making our views very well known.
"From America's perspective, each country has a sovereign right to make its own decision about how to deal with the challenge.
"The United States has an obligation to ensure that places where we operate, places where American information is, places where we have our national security risk, that they operate inside trusted networks. That's what we'll do."
Significant issues have been previously found in the Chinese firm's technology infrastructure, adding fuel to flames it could be an easy target to Beijing's communist regime to spy on western targets through a backdoor.
Earlier in the day, International Trade Secretary Liam Fox had insisted there was "much less of a difference" between the UK and US on the issue of involving Huawei than some had claimed.
The Government has yet to make an official decision on whether it will use the Beijing-linked tech giant to build telecommunications networks in Britain.
It is thought the risks of using the firm are still being assessed. It follows a leak from the Government sources which led to the sacking of Defence Secretary Gavin Williamson last week.
Also on the agenda for Wednesday afternoon's meeting was the Iran nuclear deal, with both sides said to be in agreement a change to the 2015 agreement would be a "massive step back" said Foreign Secretary Jeremy Hunt.
Mr Pompeo also insisted it was the responsibility of nations to take back any of their nationals found among the foreign fighters detained in Syria following the collapse of Islamic State.