Cash for access: David Cameron facing questions over donations from firm owned by Palestinian billionaire Electoral law states that political parties can only be funded by people registered to vote in this country, or by British companies. Jack Straw, the former home secretary, has written to the Electoral Commission calling for an investigation into allegations that the Conservative Party is prepared to accept donations from companies based overseas. It comes after a newspaper sting at the weekend showed Peter Cruddas, the Tory party co-treasurer, who has since resigned, encouraging potential foreign donors to "set up a company, employ some people to work here" as a way to circumvent those rules. Mr Straw said "The principle is very clear and in addition to this, new laws I introduced in 2009 ensured that you can't use front organisations to disguise the original source of the donation." Mr Khoury, who is worth an estimated £4 billion, is the ultimate owner of CC Property Company and Consolidated Contractors International (UK). CCI (UK) is also a Tory donor, having given £8,500 in August last year. Antoine Mattar, a British accountant, is a director of both UK companies. He told The Daily Telegraph he had been introduced to David Cameron, but it was at a party "for four or five hundred people" at The Carlton Club in London, an elite gentlemen's club for Conservative supporters. He denied that the company was created to funnel foreign money into the Tory party or that Mr Khoury gained access to Conservative ministers. He said: "We have the same philosophy as [the Conservative Party]. We don't ask for anything in return. He said Mr Khoury had never met Mr Cameron, "and if you asked him, he wouldn't know who the [British] prime minister is." Mr Mattar admitted that CC Property's only income came from CCI (UK), the British arm of Mr Khoury's construction group, which shares the same Knightsbridge address. But he insisted: "The money is not coming in from overseas - the money that comes out from our company here is nothing to do with who the ultimate owner is." Asked if CC Property had any other activities than renting space to CCI, he said: "We're in the process of buying other property." Another director of both companies is Marwan Salloum, a Lebanese solicitor who was photographed on holiday with Saif Gaddafi in 2010, before the Libyan uprising. He was photographed sailing on a yacht off the Brazilian coast with Gaddafi and several bikini-clad women. As well as donating money to the Conservative Party, CC Property gave £17,076 to the Conservative Middle East Council last October. Meanwhile CCI (UK) actively lobbies MPs and has flown MPs from both main parties to countries where it has commercial interests. Bob Spink, the former Tory and UKIP MP, took three trips to Kazakhstan, between 2002 and 2004, partly funded by Consolidated Contractors International, which donated £3,000 towards his travel costs. John Mann, Labour MP and Secretary of British Kazakhstan All-Party Parliamentary Group, joined Mr Spink on the two of those visits and Linda Gilroy, former Labour MP, also went on two of the same trips. Both Fraser Kemp, the former Labour MP and Tim Loughton, a Tory, were given flights worth £1408 to and from Tajikistan in 2009. All of the donations and foreign trips were cleared by the Electoral Commission, which polices political donations. Michael Dugher, the shadow minister without portfolio, said: "Day by day the questions for David Cameron over cash for access seem to be mounting." A Conservative party spokesman said "All donations to the Conservative Party comply fully with Electoral Commission rules. There is no question of individuals either influencing policy or gaining an unfair advantage by virtue of their financial contributions to the Conservative Party.