The Tories' commitment to a plan that could see OAPs £747-a-year better off has been plunged into fresh doubt.
Boris Johnson's spokesman refused to rule out suspending the pensions triple lock, which means pensions rise by the highest of average earnings, inflation or 2.5%.
The system is under scrutiny amid a potential 8% hike this year – the level of average wage increases as a result of the bounce back from the coronavirus pandemic.
That would mean an extra £14.37 a week, with the basic state pension rising from £179.60 to £193.97.
The pandemic-fuelled rise would hand pensioners another £747.24 a year, but experts warn it could pile extra pressure on the public finances.
Work and Pensions Secretary Therese Coffey this week admitted the Government was “looking at” ripping up the Tory manifesto promise.
The Prime Minister spokesman said: “We will obviously keep figures and numbers under review, as we always do, and take any decisions at the appropriate time.
“I think it's right that we ensure there is fairness for both pensioners and taxpayers.”
The Office for Budget Responsibility has predicted an earnings hike of up to 8% from next April, which could cost the Treasury an extra £3billion a year in pensions.
“We recognise people's concerns about what that may mean, and it's important we ensure fairness,” the PM's spokesman added.
“The Chancellor has said previously that the triple lock is Government policy, but we recognise people's concerns.”
Chancellor Rishi Sunak declined to rule out abandoning the manifesto commitment.
“The triple lock is the Government’s policy but I very much recognise people’s concerns,” he told the BBC this month.
“I think they are completely legitimate and fair concerns to raise.
“We want to make sure the decisions we make and the systems we have are fair, both for pensioners and for taxpayers.”
