Former UK Prime Minister David Cameron faced a long afternoon of questions from MPs over his lobbying for Greensill Capital, a short-term supply-chain finance company.

His first session was with the Commons' Treasury Committee, his second with the public accounts committee.

There has never been any suggestion that Cameron has broken the law in any way, but given that his office sent more than 45 emails, texts and WhatsApp messages to personal contacts in the government between March and June 2020 it's led to accusations of an inappropriate use of his privileged position.

It was described by some as "bombarding ministers and officials" and the Bank of England, including six personal SMS messages to the finance minister, Chancellor Rishi Sunak, in attempts to win business for his new employer Greensill Capital.

In his opening statement to MPs, Cameron offered no apology and made clear that personal gain was not his motivation. Rather, he explained, he wanted to do what he could through Greensill to help businesses that might start to struggle during the pandemic.

Greensill Capital has since collapsed with the loss of 440 jobs, including that of the former prime minister.

Cameron also made clear that Lex Greensill, the head of Greensill Capital, was not a contact of his when he was recruited as an adviser to Number 10 Downing Street while he was prime minister.

According to Cameron, he was brought in by the then cabinet secretary, Jeremy Heywood, and that he, himself, only met him "once or twice."

In his own evidence to the Treasury Committee earlier this week, Greensill denied his previous government role had allowed him to win contracts for his business.

He denied claims he was a fraudster, but he did admit Cameron had attended Greensill board meetings and that he and the former prime minister had traveled together on the company's private jets.

Cameron's explanations were calm but also lengthy, prompting an interruption from Labour MP Siobhain McDonagh.

"Do you not feel that you have demeaned yourself and your position," she asked, "by WhatsApping your way around Whitehall, on the back of a fraudulent enterprise, based on selling bonds of high-risk debt to unsuspecting investors?"

There was also discussion about how unusual it is for former prime ministers to have direct contact with serving chancellors.

There is no doubt that such a grilling by sitting MPs is excruciatingly embarrassing for a former prime minister, but there is no suggestion he has broken any laws.

The findings of these committees will inform public standards going forward but not pass formal judgment on those they have interviewed.