Prime Minister Theresa May raised objections to the Hinkley Point nuclear deal during the coalition government, Lib Dem ex-business secretary Sir Vince Cable has claimed.
Sir Vince said the then home secretary was unhappy about the "gung-ho" attitude to Chinese investment displayed by former chancellor George Osborne.
The ex-cabinet member was speaking after Mrs May unexpectedly delayed signing-off on the project at the last minute which sparked speculation as to whether it would go ahead.
"Certainly, when we were in government, Theresa May was, I think, quite clear she was unhappy about the rather gung-ho approach to Chinese investment that we had, and that George Osborne in particular was promoting and, as I recall, raised objections to Hinkley at that time," Sir Vince told BBC Radio 4's Today programme.
Sir Vince suggested Mrs May's more critical approach was right "once you separate that out from a kind of general prejudice against Chinese investment".
Recalling the then home secretary's stance, Sir Vince told Sky News: "There clearly was a difference and we can now see this difference being played out in the questioning of the Hinkley project.
"The handling of this has been very messy, and I'm sure it's greatly annoyed the French. And it's almost certainly ruffled the feathers of the Chinese."
Critics believe the Government has been stung by criticism of the amount of money French energy giant EDF will be paid for generating power from Hinkley - £92.50 per megawatt hour of electricity generated.
It is thought there are also security concerns about the role of the Chinese state - which has a one-third share in the project - investing in critical infrastructure in the UK.
Labour leader Jeremy Corbyn said: "The headline figures are very disturbing on the price, the price of the electricity that is going to be generated, the risk to the British taxpayer of the whole thing, and, of course, the fact that we are handing over large areas of our energy generation to the French and Chinese to control. I think we need to have some serious discussions, and will be having them."
The claims came as the boss of EDF said he understands the Government wanting more time to consider plans for a new nuclear power station.
Vincent de Rivaz has written to workers in a bid to reassure them that the £18 billion Hinkley Point project is still "strong" despite the unexpected delay.
The company's board narrowly voted to give the final go-ahead for the long-delayed project but the Government pulled back from signing the contract saying it would make a decision in the early autumn.
Mr de Rivaz said: "The new Prime Minister has been in post for just 16 days. Her full Cabinet has been in post even fewer.
"We can understand their need to take a little time. We fully respect the Prime Minister's method."
The chief executive said his message was one of confidence and promised the project would deliver high-quality jobs across the country when it was finally built.
"The very good news is that we are ready. The board's decision means that when the Government is ready to go ahead, we are ready too."
Mr de Rivaz said he had met Business and Energy Secretary Greg Clark after the minister announced the Government would "consider carefully" all parts of the project before making a decision.
Mr de Rivaz's letter said: "In April, I asked the project team in Britain and France to 'stay mobilised - keep your motivation high. Remain the professionals you are, committed to the company'.
"We have never stopped the project and the teams kept working so that they could preserve the timetable. On the site we have continued to prepare and develop the site for the construction phase.
"My message today is one of continuity and confidence. The EDF board's decision is a huge achievement and one we should be proud of. Our journey is a long one and there is a further stage. Our job now is to maintain the courage, patience and dedication that have served us so well."
Unions have warned that jobs are at risk, though Government sources insisted the delay had been agreed with the French.
Downing Street would not be drawn on Sir Vince's claims.
Business and Energy Secretary Greg Clark said: "The UK needs a reliable and secure energy supply and the Government believes that nuclear energy is an important part of the mix.
"The Government will now consider carefully all the component parts of this project and make its decision in the early autumn."
Sir Vince told The Sunday Telegraph that Mrs May had long-standing security concerns regarding China.
Referring to Chinese telecommunications giant Huawei, which is involved in a major partnership with BT, Sir Vince said Mrs May was "never completely satisfied about Huawei."
"I, and others, thought they were a good thing but I think she was worried about them," he said.
"She has expressed, in several different contexts, severe reservations about China getting too close to the UK," the ex-business secretary said.
The Sunday Telegraph reported Sir Vince saying that as home secretary, Mrs May was reluctant to relax visa rules for Chinese businessmen, but was over-ruled by former chancellor George Osborne.