Sayeeda Warsi, the co-chairman of the centre-right party and a cabinet minister without portfolio, apologised for failing to disclose that Abid Hussain and she were both shareholders in a food company before the 2010 visit.
"I accept that I should have made officials aware of the business relationship between Mr Hussain and myself, and for this I am sorry," she wrote in a letter to Cameron.
"I regret that this failure may have caused embarrassment to the government."
But Cameron called in Alex Allan, his independent adviser on ministerial interests, to "consider the issues that have been raised with respect to the ministerial code and to provide advice to me as rapidly as possible".
Under the code, ministers must avoid any conflict of interest, or the appearance of such a conflict.
Warsi, who is the first female Muslim minister in Britain and sits in the upper House of Lords in parliament, has been under mounting pressure over separate allegations about her expenses claims for house rental.
Several parliamentarians were jailed after The Daily Telegraph newspaper published details of claims in 2009 revealing how taxpayers' money was used for lawmakers' widescreen TVs, furnishings and even an ornamental duck house.
Cameron's decision to order an investigation into Warsi also raises awkward questions about why he did not take the same action against culture minister Jeremy Hunt over his controversial dealings with Rupert Murdoch's media empire.
Hunt has faced calls to resign over his communications with Murdoch's US-based News Corp. at a time when he was supposed to be making an impartial decision on the company's bid for full control of British pay-TV giant BSkyB.
COMMENTS (8)
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@Dark Knight: Relax kid..take a deep breath and have a glass of cold water. Don't generalize your childish statement.
The rightwing Pakistanis are spreading corruption even in the UK! That is called progress.
Pakistanis some how really fail to understand basic moral rules and totally ignore the law of land. And when they get caught they simply say "Oops!, I am sorry"...............
Satyamev Jayate
"Cameron’s decision to order an investigation into Warsi also raises awkward questions about why he did not take the same action against culture minister Jeremy Hunt over his controversial dealings with Rupert Murdoch’s media empire".
Awkward for whom? If you are caught stealing, then the fact that there are many thieves that have not been caught is not a valid defense in a court. Same deal. If Baroness Warsi did something which had a conflict of interest, she will be held accountable for that. Whether someone else was held accountable or not is besides the point. Without knowing the full facts of that case, most Britons would tend to trust their OM's judgment - if he has chosen not to pursue that case and chosen to pursue this one.
Serves you right after the remarks you gave about Pakistani minority men recently !
Ok Ms Warsi, Your recent claims and assertions about Pakistanis in general, triggered by some Pakistani men involved in sexual assault case, hurt a lot of feelings. This time we Pakistanis will be again targeted in media, except this time it won't be you making grandeur claims. Time to have a taste of your own medicine