Last month, Morrisons - Britain's fourth largest supermarket group after Tesco, Sainsbury's and Asda - rejected a proposed 5.52 billion pound ($7.62 billion)cash offer from Clayton, Dubilier & Rice (CD&R).
However, shares in the grocer, which trades from about 500 UK stores and employs 118,000, have since risen by over a third on hopes of a raised bid from CD&R or offers from other private equity suitors or Amazon.com Inc.
Asda was taken private in February, when Zuber and Mohsin Issa and private equity group TDR Capital completed their purchase of a majority stake from Walmart Inc.
"There is concern that regulatory bodies have insufficient oversight or powers to intervene when new owners act irresponsibly," Darren Jones, an opposition Labour Party lawmaker and chair of the Business, Energy and Industrial Strategy Committee, said in a letter to Andrea Coscelli, the chief executive of the Competition and Markets Authority (CMA).
He noted previous purchases of high street brands using significant amounts of debt, which have ultimately resulted in administration, job losses and pension fund shortfalls.
"Can you please set out which (if any) issues here merit further consideration by the CMA? Please could you also advise what powers you currently have to deal with such issues, and/ or identify what new powers you think ought to be considered so that these issues can be addressed?"
Last week Labour called on the government to confirm it will intervene in any private equity takeover of Morrisons to secure binding commitments about the buyer's business plan, on jobs and on pensions.
The government has powers to intervene in takeovers of companies on grounds including competition, media plurality, national security and pandemic response.
However, Labour wants the government to have powers to intervene where an acquisition may have long-term implications for the United Kingdom's industrial strategy.
($1 = 0.7242 pound)
(Reporting by Kate Holton and James Davey; editing by William James and Jonathan Oatis)