Lancashire West MP, Ashley Dalton, has urged the Competition and Markets Authority to look into the deal.
Dalton said: “As one of the largest private sector employers in the UK, the future sustainability of Asda is important to my constituents that work there. Their livelihoods rely on it.”
She pointed to Asda’s reported debts of £4.7bn which could swell to £11.7bn under the merger.
“The merger looks set to hugely increase the debt burden on Asda, which will threaten jobs in Skelmersdale, across West Lancs and beyond as well as the future of the company,” Dalton said.
Issa brothers-owned Asda announced its acquisition of EG Group at the end of May in a £2.27bn deal.
The supermarket giant said that it plans to invest more than £150m within the next three years to integrate the combined businesses.
Shareholders are providing a further £450m to fund the transaction, Asda said.