Presidential hopeful Sen. Bernie Sanders (I-Vt.) and the chief executive of one of his frequent targets — Walmart — found one thing to agree on Wednesday: the need for a higher minimum wage. But they diverged on how and how much.

With the retailer’s annual shareholders meeting as his backdrop, Walmart chief executive Doug McMillon called on Congress to raise the federal minimum wage of $7.25 an hour, which he said is “lagging behind” the retailer’s $11 an hour.

“It’s clear by our actions and those of other companies that the federal minimum wage is . . . too low,” McMillon said. “It’s time for Congress to put a thoughtful plan in place to increase the minimum wage.”

Minutes later, Sanders criticized Walmart for paying many of its employees “starvation wages” and said it ought to match the $15 hourly minimum already in place at Amazon and Costco. The senator was invited to the Rogers, Ark., meeting by Walmart workers who had asked him to introduce a proposal that would give hourly employees a seat on the company’s board.

“Despite the incredible wealth of its owner, Walmart pays many of its employees starvation wages,” Sanders said. “Surely Walmart can afford to pay its employees a living wage of at least $15 an hour.”

Walmart, which is based in Bentonville, Ark., raised its starting hourly wage from $9 to $11 last year. The median pay was $21,952 last year, a 14 percent increase from the previous year, according to company filings. McMillon, by comparison, took home $23.6 million last year.

It also has started offering paid parental leave and $1-a-day college courses to attract and keep employees in a competitive job market with record-low unemployment.

On Wednesday, McMillon said any increases to the federal minimum wage should be phased in gradually and factor in cost-of-living differences “to avoid unintended consequences.”

Sanders has long argued that the nation’s largest private employer should be doing more for its 1.5 million U.S. workers. Last fall, he introduced the Stop Walmart Act, which would prohibit corporations from buying back their own stock — which drives up share prices and ultimately benefits shareholders — unless they pay workers at least $15 an hour, offer seven days of paid sick leave and limit executive pay.

“We have made progress in the last year in raising the minimum wage in this country,” Sanders said in a phone interview before Wednesday’s shareholders meeting. “There is no reason in the world why Walmart should not do the same.”

Walmart’s largest competitor, Amazon, increased its starting pay to $15 an hour in November, after Sanders introduced legislation that would require the company to pay its workers a “living wage.” (Amazon founder and chief executive Jeff Bezos owns The Washington Post.)

In April, Bezos called on other large retailers to follow suit.

“I challenge our top retail competitors (you know who you are!) to match our employee benefits and our $15 minimum wage,” he said in a letter to shareholders. “Do it! Better yet, go to $16 and throw the gauntlet back at us. It’s a kind of competition that will benefit everyone.”

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