(Adds detail) LONDON, Sept 7 (Reuters) - Britain will not raise state retirement pensions in line with wages next year, but will instead increase them by the rate of inflation or 2.5%, whichever is higher, work and pensions minister Therese Coffey said on Tuesday. Coffey told parliament she would introduce legislation to temporarily override a “triple-lock” formula which would have seen state pensions rise by 8% or more next year, due to what she called an “irregular statistical spike” in earnings caused by the COVID-19 pandemic. “For 2022-23 it will ensure the basic and new state pensions increase by 2.5% or in line with inflation, which is expected to be the higher figure this year,” she said. The triple lock would return from 2023-24, she added. Prime Minister Boris Johnson promised in December 2019 election campaign to keep a ‘triple lock’ on state pensions which would rise by the highest of earnings, inflation or 2.5%. The promise did not specify what measure of wage growth would be used, but the one which has been used in the past - average weekly earnings published by the Office for National Statistics - has been heavily distorted during the pandemic. Average weekly earnings showed annual growth of 8.8% in the three months to June, but the underlying rate absent these distortions was more like 3.5%-4.9%, the ONS said last month. Most workers who were on furlough a year ago are now back at work, and so are now receiving full pay rather than reduced furlough wages. Job losses were mostly among the lower paid - artificially boosting average pay levels among those remaining. (Reporting by David Milliken Editing by William Schomberg and Michael Holden) Our Standards: The Thomson Reuters Trust Principles.