A private health company that became the biggest corporate funder to the Liberal Democrats is a client of the party treasurer’s government lobbying business, The Times has learnt.

Lord Clement-Jones, the Lib Dems’ chief fundraiser since 2005, has come under scrutiny because he helped to get a peerage for a director who sits on the sister companies of Alpha Healthcare, the Lib Dems’ donor.

The discovery of the lobbying link comes as an all-party committee of MPs is to meet on Thursday to consider whether more light should be shed on politicians who are also lobbyists.

In January an investigation by The Times raised concerns about how Lord Hameed, a private hospital chief, was helped to a crossbench peerage by senior Liberal Democrats.

Lord Clement-Jones seconded his nomination. Lord Dholakia, the only Lib Dem on the Lords Appointments Commission, praised the interfaith work of Khalid Hameed when his name came up as a candidate. None of the three declared to the commission that Alpha Healthcare was a donor to the Lib Dems. The company became the main corporate backer of the party with gifts of nearly £400,000. The biggest gift of £125,000 came after the peerage was confirmed.

Lord Hameed, who sits on both of Alpha Healthcare’s sister companies, insisted that he did not know about its donations. Lord Dholakia said that he too was in the dark. But Lord Clement-Jones said he thought that he probably had told Lord Dholakia about the gifts.

The Times has since learnt:

— Lord Dholakia made a “full written declaration” of how he was acquainted with Lord Hameed after the commission had recommended the hospital boss for a peerage. A commission source said that this accorded with normal practice;

— The commission’s internal inquiry into the Times investigation concluded that there was no wrongdoing, but omitted to interview Lord Clement-Jones or ask the newspaper for evidence;

— A freedom of information request for the names of everyone Lord Clement-Jones has supported for a peerage was rejected by the commission because it would “breach confidence”.

The ties between Lord Clement-Jones and Alpha Healthcare appear to fly in the face of the Lib Dems’ motion at their 2001 conference that asked peers to refrain from professional lobbying. The Lib Dems’ federal executive regarded that request as “unenforceable”. It noted the safeguards in the Lords’ declaration of interest requirements and agreed to take no further action.

When The Times first began investigating Alpha Healthcare’s donations last autumn, a reporter visited the homes in London of the brothers Dhruv and Bhanu Choudhrie. They run C&C Alpha, a group of companies ultimately owned by entities registered in the tax havens of Guernsey and the British Virgin Islands. Alpha Healthcare is part of the group.

The brothers’ spokesman, Eben Black, called The Times to say that he represented C&C Alpha. Mr Black is also head of media at the global government relations department of DLA Piper, a multinational law firm that offers lobbying services. Lord Clement-Jones is the department chairman.

DLA Piper said it provides media relations services to the Choudhries’ group of companies.

Mr Black said that the first time one of C&C Alpha’s companies became a client was in February 2006. Alpha Healthcare went on its books in September 2007. Alpha Healthcare’s donations to the Lib Dems began in March 2004 and ended in May 2007, according to Electoral Commission records.

Lord Clement-Jones makes no declaration concerning C&C Alpha in the House of Lords register of interest of clients for whom he provides parliamentary services. He said: “I do not act personally for C&C Alpha.” The Lib Dem party treasurer denied that there was a conflict of interest in his roles as treasurer, parliamentarian and lobbyist. “Members of the C&C Alpha Group happen to be both donors to the Liberal Democrats and clients introduced by me to DLA Piper,” he said. “I would ask why the firm should not provide professional services to them, whether legal or media relations services.”

The Lords Appointments Commission told The Times that in 2005 “it was noted that Lord Dholakia was acquainted with Dr Hameed”. This was brought to the commission’s attention. Lord Dholakia also attended the meeting in December 2006 at which Lord Hameed was recommended for a peerage. In February 2007, when the peerage was announced, Lord Dholakia made a written declaration that he knew Lord Hameed as an acquaintance and had “attended a number of his lectures [mainly on faith issues]”.

Lord Dholakia, deputy leader of the Lib Dems in the Lords, told The Times: “I had no knowledge of any donations to the Liberal Democrats. My acquaintance with Lord Hameed, whom I had met half a dozen times before, were fully declared to the commission. The correct procedure was followed with a written statement for the register of members’ interests.This requires members to put in writing what has been made known verbally before.”

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