Bernie Sanders, a leading Democratic presidential candidate, is preparing to gatecrash Walmart’s annual meeting to demand the world’s biggest retailer increase its 2.2 million workers “poverty wages”.

Sanders is expected to attack the multi-billionaire Walton family, who own Walmart, for paying its full-time workers an average of just $14.26 per hour (£11.25) while handing the chief executive, Doug McMillon, a $23.6m pay package.

McMillon’s pay is 1,076 times that collected by the median worker, and makes him by far the best paid person in Arkansas, where Walmart is based and where the AGM will be held.

“Walmart workers are sick and tired of being paid poverty wages, while the Walton family is worth over $170bn,” the Vermont senator said in a tweet. “I’m honored to have been invited by Walmart workers to demand they have a seat on the company’s board.”

Sanders, a longtime critic of working conditions at the nation’s biggest private employer, will introduce the workers proposal at the annual meeting in Rogers, Arkansas, on 5 June. However, there is very little chance of the proposal attracting enough votes.

Sanders will speak as a proxy for Cat Davis, a Walmart employee who filed the latest action. “We should have the power to decide what happens at the company many of us have given our working lives to,” Davis said in a statement. “Associates deserve more from Walmart than we’re getting right now, especially as we’re the ones who create the company’s profits. Senator Sanders recognises that.”

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Sanders has repeatedly highlighted Walmart as an example of startling inequality in America comparing the Waltons’ vast fortune with the supermarkets low paid workers, many of whom get by on government-issued food stamps and Medicaid – the health cover programme joint-funded by state and federal government. Sanders often claims that the Walton family collectively has more wealth than the bottom 40% of Americans.

A spokesman for Walmart, which owns Asda in the UK, said: “If Senator Sanders attends, we hope he will approach his visit not as a campaign stop, but as a constructive opportunity to learn about the many ways we’re working to provide increased economic opportunity, mobility and benefits to our associates.”

In addition, institutional shareholder advisory services Glass Lewis and Institutional Shareholder Services (ISS) have recommended that shareholders vote against Walmart at the meeting. Glass Lewis has advised investors vote down Walmart’s remuneration plans stating that there is a “pay and performance disconnect”. ISS has also advised shareholders vote for a motion demanding that Walmart strengthens oversight to prevent sexual harassment in the workplace.

