Former Pensions Minister Sir Steve Webb, a partner at retirement consultancy lcopLCP, has warned that axing or significantly diluting the pensions Tripe Lock would mean an additional 10m pension savers will face an “inadequate” pension.

Speaking recently at a Society of Pension Professionals (SPP) webinar on the State Pension, Sir Steve said the Triple Lock had maintained some form of pension adequacy for millions of people.

Ditching it could harm millions as their pension income would drop.

He said that while government figures currently indicate around 15m people will not have an adequate income in retirement, this is based on the Triple Lock mechanism lasting forever.

The Triple Lock mechanism means that the State Pension rises annually by the highest of three different measures: the Consumer Prices Index, average earnings growth or a guaranteed 2.5%. It provides an annual boost to the State Pension.

Sir Steve warned that if the Triple Lock is replaced with annual increases only in line with inflation (CPI), as some have suggested, the number of people who will have an inadequate retirement income leaps from 15m to over 25m, a 10m increase. Sir Steve described the situation as “living in a fools paradise.”

Sir Steve was one of several pension experts taking part in the SPP webinar attended by about 200 pension professionals.

The event also heard from Phil Warner from Dalriada Trustees who talked about the history of pensions, starting with the early forerunners to the State Pension from the Chatham Chest of the 1500s and Poor Laws to the Old Age Pensions Act of 1908 which was non-contributory and only payable to those “of good character” from age 70.

Stuart Earle, partner at Eversheds Sutherland and chair of the event, said: “We are moving ever closer to the original State Pension Age of the early 1900s (which was 70) and, as Sir Steve highlighted, the ticking time bomb of inadequate pension saving is probably worse than the government and others think.”