Labour has been urged by Tony Blair’s thinktank to scrap the pensions triple lock amid mounting pressure on government finances.

With the Iran war threatening to derail public spending plans, the Tony Blair Institute (TBI) said the “unaffordable” manifesto pledge to maintain the triple lock should be torn up as part of a wider overhaul of the state pension.

The triple lock guarantees that the basic and new state pensions will rise every April by whichever is highest: inflation, average wage growth or 2.5%.

Saying change was “unavoidable” as Britain’s steadily ageing population drove up the cost of the policy, the thinktank suggested a pre-election pact should be made between the main political parties to ensure the triple lock did not continue past the next general election.

Introduced by George Osborne , under the Conservative-Liberal Democrat coalition in 2010, in recent years, the policy has added billions of pounds to annual government spending amid inflation shocks from the Covid pandemic and…