LONDON, May 10 (Reuters) - The Guardian newspaper reported on Tuesday that John Allan, the chairman of Britain's biggest retailer Tesco, was facing claims of inappropriate behaviour from four women.

One of the allegations relates to Allan's conduct at Tesco and three to his time at the Confederation of British Industry (CBI), where he was president from 2018-2020.

Responding to questions from Reuters, Tesco said Allan "strongly denies" an allegation that he touched a senior female Tesco employee's bottom at a group annual shareholder meeting in 2022, and that there have been no complaints about Allan's conduct during his eight years as chairman.

The Guardian, which did not identify its sources, said Allan was also alleged to have grabbed the bottom of a woman at a CBI dinner in 2019 and to have made inappropriate remarks to female members of CBI staff on two other occasions.

A spokesperson for Allan said in a statement the Tesco chairman had been "mortified" after making a comment to a female CBI colleague in 2019 for which he immediately apologised. The spokesperson said the woman concerned agreed that the matter was closed and no further action was taken.

"Regarding the other claims, they are simply untrue," the spokesperson said.

"Even so, Mr. Allan requested that Tesco and (law firm) Fox Williams – who were instructed by the CBI to conduct an investigation following various allegations – investigate them. Fox Williams decided not to," he said.

The CBI hired Fox Williams to investigate accusations of serious workplace misconduct last month. One of Britain's best-known business organisations, the CBI is now under police investigation and battling for its survival as a number of big firms cut ties.

A spokesperson for Fox Williams said it was not correct that it had decided not to investigate the allegations, but that its work for the CBI had been conducted within strict parameters.

"As a result, we were not permitted to speak to all individuals involved in the allegations," the spokesperson said. "Mr Allan was provided with the opportunity to give an account to the CBI via Fox Williams which, as far as we are aware, he has chosen not to do."

Allan's spokesperson said his lawyers had contacted Fox Williams twice in April but that no meeting had been set up, although the firm had offered to forward a statement from Allan to the CBI.

Fox Williams later confirmed that Allan's lawyers had contacted the firm.

One of Britain's highest-profile corporate names, Allan, 74, is often featured in British media commenting on retail and general business matters. He also chairs housebuilder Barratt Developments, where he is due to step down in September.

Allan is expected to step down as Tesco chairman next year, having completed nine years in the job.

"At Tesco, we are committed to ensuring all colleagues are respected and feel safe at work," a Tesco spokesperson said in a statement. "John Allan's conduct has never been the subject of a complaint during his tenure as chair of Tesco." (Reporting by Sarah Young and James Davey; Editing by Catherine Evans and Alexander Smith)