Barack Obama has urged Sir Terry Leahy, Tesco’s chief executive, to meet American trade unions campaigning for recognition at the supermarket group’s fledgeling Fresh & Easy chain in the US.

In an extraordinary letter to one of Britain’s most respected business leaders, the Democratic presidential contender “strongly requests” that Sir Terry review his decision not to engage with the union movement.

In the letter, seen by The Times, Mr Obama said: “It is in your interest to ensure that the communities and the leaders of workers in the industry are heard and that their concerns are heard and respected.

“I am aware of Tesco’s reputation in Britain as a partner to unions. I would hope that you would bring those values to your work in America.”

The move marks the second time that Mr Obama has intervened on behalf of the powerful United Food and Commercial Workers’ Union (UFCW) in its dispute with Tesco.

The US senator wrote to Tim Mason, Fresh & Easy’s chief executive, urging him to engage with local community leaders in California eight months ago, shortly before the first Fresh & Easy store opened near Los Angeles. The UFCW is furious at its failure to gain recognition at Fresh & Easy and claims Tesco is being “two-faced”, given its partnership deal with Usdaw, the UK shopworkers’ union.

The UFCW has helped to fund the Obama campaign for the White House, yet union officials yesterday insisted that Mr Obama would have written to Sir Terry regardless of being involved in the presidential campaign.

James McLaughlin, president of the UFCW’s Arizona Local, said: “This is consistent with what he would have done as a community organiser in the state of Chicago.”

Mr McLaughlin added: “We are not looking to be a problem. We are looking to build partnerships with good employers with the positive track record we felt Tesco had. We are just looking to have some dialogue.”

Tesco yesterday signalled that its stance would not be changing despite Mr Obama’s personal plea. A spokesman said: “We strongly believe that union membership is a matter of individual choice and if our people want to join a union, then they can and will. All the signs so far are that there is little interest in doing so.”

The controversy is almost certain to be raised by UFCW officials due to attend Tesco’s eagerly awaited annual shareholder meeting in Birmingham tomorrow. The meeting is expected to be one of the most colourful of this year’s corporate calendar, with Hugh Fearnley-Whittingstall, the celebrity chef, having already tabled a resolution calling on Tesco to improve its chicken welfare standards.

Unite, Britain’s biggest trade union, will today unveil its own campaign attacking the supermarket group over what it says are Dickensian working conditions at Brown Brothers, a Scottish meat supplier. Staff at the company’s plant in Dumfriesshire have to clock off to go to the lavatory and Unite has vowed to present Sir Terry with a “golden loo” at the meeting.

— Pirc, the corporate governance watchdog, has called on members to vote against re-election of Sir Stuart Rose at Marks & Spencer’s annual meeting next month in protest over his executive chairman role at the group. Pirc said that the decision to combine the chief executive and chairman position represented a “dangerous concentration of power” that could unbalance the boardroom.

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