Tony Blair signed a 'secret contract' with a Saudi Arabian oil firm - which promised him £41,000 a month and a cut in successful negotiations

Tony Blair has amassed a personal fortune since standing down as prime minister – often acting as an adviser to controversial businesses and regimes.

But yesterday the hefty fees he charges to act as a go-between were revealed.

A previously secret contract with a Saudi oil company headed by a member of the country’s royal family has been leaked showing Mr Blair charging £41,000 a month and 2 per cent commission on any of the multi-million-pound deals he helped broker.

The emergence of the Saudi deal led to new criticism of Mr Blair’s role as a Middle East envoy, but he strongly denied there is a conflict of interest.

The contract between Tony Blair Associates (TBA) and PetroSaudi signed in November 2010, said Mr Blair would personally arrange introductions to his contacts in China, such as senior politicians.

He had already attracted scathing criticism after it emerged that he had given Kazakhstan’s autocratic president, Nursultan Nazarbayev, advice on how to manage his image after the slaughter of 14 unarmed civilians.

Mr Blair has said claims that he is worth £100million are ‘greatly exaggerated’. But the Saudi contract shows how much he has been able to charge for his services.

Since leaving Downing Street in 2007, he has amassed a fortune including a property portfolio of 31 homes worth at least £25million.

He is one of the world’s best paid speakers – earning up to £150,000 a speech – and has secured advisory roles with US investment bank JP Morgan and Swiss insurer Zurich International.

The Saudi contract stated that TBA would help find potential sources of new investment and added that Mr Blair would make ‘introductions to the senior political leadership, industrial policymakers, corporate entities and other persons in China identified and deemed by us and you to be relevant to PetroSaudi’s international strategy’.

The firm agreed it would not divulge his role without permission.

Deal: Tony Blair in 2010 with King Abdullah of Saudi Arabia, right. Mr Blair signed a contract with PetroSaudi, a firm founded by his son

Tony Blair and his wife Cherie, pictured yesterday walking through Downing Street on their way to the annual Remembrance Sunday service at the Cenotaph memorial in Whitehall, London

The former Labour Party leader (centre) stands shoulder to shoulder with George Osborne, Ed Miliband, Nick Clegg and John Major at the service amid claims he 'signed a secret contract' with the oil firm

The former Labour Party leader signed the deal with PetroSaudi, which was co-founded by the son of the King of Saudi Arabia - Prince Turki bin Abdullah Al Saud (pictured centre, shaking hands)

The contract read: ‘Each party will ensure that no announcements, statements or documentation containing any reference to either party or to Tony Blair will be published or made without the prior express written consent of the other party.’

The oil firm was founded by Saudi businessman Tarek Obaid and Prince Turki bin Abdullah Al Saud, a son of Saudi Arabia’s King Abdullah, and has projects in Ghana, Indonesia, Venezuela and Tunisia.

Critics have already said Mr Blair is not suitable for his role as a Middle East peace envoy, in which he is a representative of the quartet of the UN, the EU, the US and Russia, because of his business interests in the region.

Oliver Miles, a former ambassador to Libya, who signed a letter in June that argued Mr Blair’s responsibility for the Iraq crisis and lack of transparency of his interests, said this was the latest example of why he was wrong for the unpaid role.

PetroSaudi (pictured is one of its ships) asked that Blair personally introduce them to his Chinese contacts

‘The fact this was kept a secret, or was intended to be kept secret, was a mistake,’ he told the Sunday Times.

But a spokesman for Mr Blair stressed the consultancy work was related to China not the Middle East. He said: ‘Tony Blair Associates worked for PetroSaudi for a period of months over four years ago.

‘This was in connection with an issue in the Far East and nothing whatsoever to do with the Middle East or the unpaid ex-officio role of Tony Blair for the quartet in Palestine.’

PetroSaudi said Mr Blair was engaged on a confidential basis to help develop business in China and the work lasted ‘about four or five months maximum’.

Saudi Arabia has come under fire over its human rights record. Amnesty International has said that more than 2,000 people were executed there between 1985 and 2013.