US retail giant Walmart on Tuesday said Binny Bansal, CEO of Flipkart Group, India's biggest ecommerce player that it acquired this May, has resigned from the position with immediate effect.

The decision of Bansal, a co-founder of the company, follows an independent investigation done on behalf of Flipkart and Walmart into an allegation of serious personal misconduct, Walmart said in a statement, adding that he strongly denied the allegation.

Watch: Walmart is wholeheartedly supporting Flipkart's strategy, says co-founder Binny Bansal

"While the investigation did not find evidence to corroborate the complainant’s assertions against Binny, it did reveal other lapses in judgement, particularly a lack of transparency, related to how Binny responded to the situation. Because of this, we have accepted his decision to resign," it said.

In July this year, an allegation of sexual assault was brought against Binny Bansal and the investigation started after that, Walmart told CNBC-TV18, adding that it does not involve Flipkart employee.

The investigation was done by a global law firm in coordination with Walmart and Flipkart board and it could not corroborate the allegation of sexual assault, the company said.

The investigation concluded recently and Binny Bansal informed Flipkart associates on Tuesday morning about his decision to leave the company, Walmart added.

A person in the United States familiar with the Walmart investigation said "a claim of sexual assault against Binny" came to its attention in late July. The accusation dated to a few years earlier and was made by a former Flipkart associate, who was not with Flipkart at the time, the person added.

Walmart said in a filing that it conducted its own investigation into the allegations, without saying what the accusations were.

"While the investigation did not find evidence to corroborate the complainant's assertions against Binny, it did reveal other lapses in judgment, particularly a lack of transparency, related to how Binny responded to the situation." Walmart said.

"Because of this, we have accepted his decision to resign." The person familiar with the matter at Walmart said that Bansal had hired two private security firms at the end of 2016, "to make this matter go away," referring to the alleged assault claim. The person did not disclose the names of the security firm or the parties involved and Reuters was unable to confirm them.

"Binny had an opportunity to disclose these allegations to us when we were in talks (to invest in Flipkart)..but he did not," the person said.

Ananth Narayanan will continue as the CEO of Myntra and Jabong, and will report to Krishnamurthy. In 2007, Binny co-founded Flipkart with Sachin Bansal and was serving as the chief operating officer until 2016 and was promoted to chief executive officer. In January 2017, he was promoted to group CEO of Flipkart. Bansal’s resignation marks the exit of co-founders from Flipkart. Sachin Bansal had exited the company they founded after selling his stake to Walmart.

Walmart acquired about 77 percent of Flipkart in May, for nearly $16 billion in what was the US retail giant's largest-ever deal and a move to take on arch rival Amazon in a key growth market.