Conservative MP Jacob Rees-Mogg has been reported to the parliamentary standards commissioner, according to a letter passed to BuzzFeed News.
The allegations relate to claims that Rees-Mogg broke rules by failing to declare a financial interest in oil and tobacco companies when speaking in the House of Commons.
The Tory MP for North East Somerset works part-time for hedge fund Somerset Capital Management, for which he is paid over £120,000 a year, in addition to his job as an MP. The hedge fund, which he co-founded, has tens of millions of pounds invested in tobacco, oil, and coal-mining companies.
Labour claims Rees-Mogg has repeatedly spoken out on behalf of those industries in the House of Commons while failing to mention his involvement in a hedge fund that invests substantial sums of money in the same sectors. MPs are expected to declare any relevant financial interests before taking part in Commons debates.
Sheila Gilmore, Labour MP for Edinburgh East, has now reported Rees-Mogg to the parliamentary standards commissioner, saying "one could reasonably think that his comments and positions on these issues might be influenced by his financial interest, in which case a relevant financial interest should have been declared".
During one House of Commons debate Rees-Mogg attacked proposals to force tobacco firms to sell cigarettes in plain packets, saying it is "taking a freedom away from the British people". Separately, he opposed a rise in tobacco duty, saying the "measure is regressive and hits some of the poorest people in the country".
On neither occasion did he declare a financial interest, even though Somerset Capital Management has £23.3 million invested in major tobacco firms.
Labour also highlighted occasions when Rees-Mogg backed plans to allow deep-sea mining and opposed green energy measures without declaring that Somerset Capital Management holds millions of pounds of shares in coal-mining and oil firms.
In her letter to the standards watchdog, Gilmore said Rees-Mogg has consistently "taken the position advocated by the industry he has a financial interest in through his company".
"Mr Rees-Mogg appears to have failed to declare a relevant financial interest on a number of occasions," she wrote.
Neither Rees-Mogg nor the Conservative party have responded to requests for comment.
Read the letter from Labour suggesting Rees-Mogg has "failed to declare a relevant financial interest" below:
Jim Waterson is a politics editor for BuzzFeed News and is based in London.
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