THE PUBLIC is owed a “full and frank” explanation about the relationship between Government and private sector lobbying, Westminster’s ethics chief has said.

Lord Pickles, chairman of the committee which vets the appointment of senior ministers and officials, told MPs “immediate address” was required to introduce greater transparency over the relationship between Government and businesses.

The Prime Minister has agreed with the peer’s remarks, saying the government needs to understand the relationship.

It comes amid the growing row over former Prime Minister David Cameron’s attempts to lobby the Chancellor and arrange drinks with the Health Secretary on behalf of collapsed finance firm Greensill Capital, for which he is employed.

It has emerged that last year the former Conservative PM sent texts to Rishi Sunak, the chancellor, and “informally” phoned two other Treasury ministers, asking for Greensill Capital to get the largest possible allocation of government-backed loans under the Covid corporate financing facility.

He also lobbied a No 10 aide, and in 2019 took Lex Greensill to a “private drink” with Matt Hancock, the UK Government health secretary.

It has also emerged that the former head of government procurement Bill Crothers began working for collapsed firm Greensill as a part-time adviser in September 2015 – a move approved by the Cabinet Office – and did not leave his Civil Service role until November that year.

The approval of the work meant that, when Mr Crothers took up a job with Greensill later, it did not need to be approved by Lord Pickles’ Advisory Committee on Business Appointments (Acoba).

The Conservative peer warned that Mr Crothers’ case highlighted “a number of anomalies within the system” and predicted that it was unlikely to be an “isolated” scenario.

He told MPs that “immediate address” was required to introduce greater transparency over the relationship between Government and businesses.

The Prime Minister, asked about Lord Pickles’ comments, told broadcasters: “I think the most important thing is for us to get to the bottom of it properly and I want all ministers and civil servants to be making the information that needs to be known, known to Mr Boardman, and let’s see what he has to say.

“You’re absolutely right, we need to understand what’s gone on here.

“I agree thoroughly with Lord Pickles,” Mr Johnson said, during a visit to the Britannia Royal Naval College in Devon.

Mr Johnson’s endorsement comes after a series of investigations were announced into the Greensill affair.

As well as the review commissioned by Downing Street, led by lawyer Nigel Boardman, the Public Administration and Constitutional Affairs Select Committee (PACAC), Public Accounts Committee (PAC) and Treasury Committee have all announced probes.

The PAC said it intended to invite Mr Cameron to give evidence during its inquiry.

A spokesman for Mr Cameron previously said he would respond “positively” to any request to give evidence to any of the inquiries that are taking place once the terms of reference have been established.

The former Tory party leader has insisted he did not break any rules but acknowledged there are “lessons to be learned”, and that as a former prime minister, any contacts with Government should be through the “most formal channels”.

Mr Johnson’s own concerns over the Greensill affair have led to Cabinet Secretary Simon Case calling on all Whitehall departments to notify him of any senior officials with paid jobs outside Government by the end of the week.

Lord Pickles said the public was “entitled” to know the arrangements for second roles being approved by the Cabinet Office, such as in Mr Crothers’ example, and called for a “full and frank” explanation.