Press scrutiny of his family apparently prompted Labour leadership frontrunner to withdraw from the race last week.
Explaining his decision to withdraw, he said: “As a member of the shadow cabinet, I am used to a level of attention which is part and parcel of the job. I witnessed the 2010 leadership election process close up and thought I would be comfortable with what it involved.
"However, since the night of our defeat last week, I have been subject to the added level of pressure that comes with being a leadership candidate.
"I have not found it to be a comfortable experience.
"One can imagine what running for leader can be like, understand its demands and the attention but nothing compares to actually doing it and the impact on the rest of one's life.
"Consequently, after further reflection I am withdrawing my candidacy."
According to Channel 4 political correspondent Michael Crick, Umunna was upset that journalists doorstepped his mother, his girlfriend’s parents and her 102-year-old grandmother.
New Statesman political editor George Eaton said: “No tabloid stories behind Chuka withdrawal, I’m told. Just immense media pressure (e.g. Daily Mail doorstepping mum)."
The Daily Mail has since contacted Press Gazette to say that it did not doorstep Umunna's mother.
Following Umunna’s withdrawal from the race on Friday there had been speculation that it had been prompted by a Sunday newspaper exposé.
The Mail On Sunday and and Sun on Sunday both probed Umunna’s private life yesterday with coverage, but neither revealed any scandal involving the MP.
The Mail On Sunday reported that he frequents a “decadent” City private members' club called M Den where Cognac costs up to £4,000 a bottle.
The Sun on Sunday reported yesterday that he accepted a £2,500 donation from a tax-planning company called Signature Tax.
A representative from the company was filmed by the paper advising a reporter posing as a Bangladeshi businessman how to take advantage of their “non-dom status”.
The paper also noted that the law firm Umunna's girlfriend works for has criticised Labour employment policy.
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