BANGALORE/MUMBAI: A wilful defaulter tag may force UB Group boss Vijay Mallya to quit the boards of India's largest alcoholic beverage companies, dealing a big blow to the tycoon whose jet-setting lifestyle once won him many young admirers.Mallya, 58, chairs the board of United Spirits Ltd (USL) and United Breweries Ltd (UBL), the market leading liquor and beer makers, in which Diageo Plc and Heineken are the major shareholders. At USL -- which he sold to Diageo in a $3 billion deal -- a new board of directors is digging into the company's past money trails.Three lenders — State Bank of India , Punjab National Bank and United Bank of India — have sought to slap the 'wilful defaulter' tag on Mallya. He has already challenged United Bank of India's move in the court and may follow suit with the other two.USL has not filed audited financial results for the last financial year and the first quarter this year as the board is uncertain on how to treat the transactions with UB Holdings Ltd, the Bangalore-headquartered parent of Mallya's empire, which is stuttering under the weight of the grounded Kingfisher Airlines. The ill-fated airline saw Mallya and his companies soak up debt and execute corporate guarantees, which started unraveling two years ago.A spokesperson for Mallya said he would not comment, while a detailed questionnaire emailed on Friday remained unanswered. Diageo spokesperson declined to comment on speculation.“RBI guidelines and Companies Act suggest that wilful defaulter won’t attract automatic disqualification unless there is criminal conviction. But shareholders and creditors can demand the removal citing the negative business impact it carries,” Shriram Subramanian, MD, InGovern Research Services, a firm that advises large investors on corporate governance said.Any company with a wilful defaulter on board cannot access banks and even capital markets for funding needs.“We are following developments on this topic, but do not wish to comment at this stage,” Heineken financial communications manager Christine van Waveren said.Dutch brewer Heineken is the largest shareholder in UBL. Mallya being declared a wilful defaulter would narrow UBL’s funding avenues at a time when the company is facing growth challenges and competitive heat from rivals like Carlsberg.Diageo, listed on London and New York stock exchanges, and controlling the USL board, is unlikely to rescue Mallya's chair if the banks pronounce him a wilful defaulter after the Department of Financial Services asked them to do so, people familiar with the matter said. Mallya, a veteran of several boardroom battles, is the only UB nominee on the 12 member board appointed after the Diageo takeover.Sources said Mallya’s alliance with Diageo is “blow hot, blow cold at best” with the latter keeping close guard over important corporate developments, including the recent open offer announcement.“Diageo wouldn’t like the consequences of Mallya being declared wilful defaulter. It will have to negotiate if it wants Mallya to be out. If Mallya is determined to continue, then the shareholders agreement and its terms would come to play,” sources that are directly part of the unfolding developments added.Most eyes will be focused on Diageo, which is already grappling with a delay in USL financial results, which ought to reflect on the consolidated financial performance of the world’s largest liquor company. Sources said both Mallya as well as the independent directors were uncomfortable with the clauses suggested by auditor KPMG regarding the past money trails, with the latter seeking more details about receivables from Mallya’s investment company.