Boris Johnson has survived the first Conservative rebellion of the new Parliament over the involvement of Chinese telecoms firm Huawei in the UK's 5G network.
Conservative critics led by former party leader Sir Iain Duncan Smith tabled an amendment seeking to ban "high-risk vendors" from the system after 2022.
Despite 38 Tories rebelling, ministers won with a majority of 24 on Tuesday after moving to head off a revolt over fears Huawei is a risk to UK security.
MPs have voted against Amendment 1 of the Telecommunications Infrastructure (Leasehold Property) Bill by 306 votes to 282 votes.
See the text of this amendment below ⬇️⬇️⬇️ pic.twitter.com/gWmddrm9rX
— UK House of Commons (@HouseofCommons) March 10, 2020
The Prime Minister was able to fend off the revolt from within his own party thanks to the 80-strong majority won at the December general election.
Critics are concerned that his decision to allow Huawei to supply "non-core" elements of the 5G network could jeopardise security because of the firm's ties to the Chinese state.
The White House has banned the firm from US telecoms networks and has been highly-critical of the Government's decision, which came despite intense lobbying from the States.
Sir Iain had warned MPs that the rebels were "genuinely concerned" about the involvement of the firm he described as being "essentially almost completely owned" by Chinese trade unions controlled by the state.
"The reality is that when it comes to security versus cost, my view is security wins every single time because I worry when we start compromising security," he added.
Conservative former trade secretary Liam Fox urged the UK to "avoid the risk" by not using Huawei rather than seeking to mitigate it.
"In order to achieve greater trade with China, we do not need to sacrifice our national security by including Huawei as part of that risk," he added to the Commons.
Ahead of the vote defeated by 282 votes to 306, Culture Secretary Oliver Dowden wrote to Tory MPs setting out the measures the Government was taking to restrict Huawei's involvement.
And he restated the commitment to see the firm replaced by competitors over time.
"I wish to stress again that the Government is clear-eyed about the challenges posed by Huawei," Mr Dowden wrote.
"That is why the National Security Council made a decision to: exclude them from the security critical network functions in 5G networks, and reduce their presence in other network functions up to a strict market share cap of 35%.
"This position is based on the comprehensive security advice provided by the cyber security branch of GCHQ, the National Cyber Security Centre."
One of the rebels, backbencher Bob Seely, welcomed the "strong first showing" in "substantially" cutting the Government majority as he eyed future opportunities.
Damian Collins, a fellow Tory who voted against the Government, warned a further rebellion could follow unless more concessions were made.
"I think we have to expect looking at what we've seen today is there will be further amendments put to the Government Bill in the summer when it comes," he told BBC Radio 4's PM.
"But there are of course a number of months now for further discussion to take place, and I think the vote today demonstrated quite a significant strength of opinion in the House on this issue."
Huawei hit back at allegations, with vice president Victor Zhang saying: "An evidence-based approach is needed, so we were disappointed to hear some groundless accusations asserted.
"The industry and experts agree that banning Huawei equipment would leave Britain less secure, less productive and less innovative."
Senior Tories to join Sir Iain in voting against the Government included former Cabinet ministers Damian Green and David Davis, Commons Foreign Affairs Committee chairman Tom Tugendhat and Tory backbench 1922 Committee chairman Sir Graham Brady.
Their move reflects widespread misgivings across the party over the decision, with fears that it could give China a "backdoor" to spy on the UK's telecoms network.