DAVID Cameron has signed up for potentially lucrative public speaking engagements in the US with the same company that helped George Osborne make half a million pounds since being sacked as Chancellor.

The former Prime Minister joins predecessors Tony Blair and Gordon Brown on the books of the Washington Speakers Bureau, whose clients can earn six-figure sums addressing well-heeled business audiences.

The Advisory Committee on Business Appointments (Acoba) has given Mr Cameron, who was Witney MP from 2001 to September this year, clearance to take up work with the organisation.

On its website, the bureau describes Mr Cameron as 'one of the most prominent global influencers of the early 21st Century'.

It added he was able to offer 'lessons in leadership at an extraordinary and turbulent time in global affairs – not least on building economic strength; creating inward investment across the UK and Europe against the backdrop of an emergent Russia and China; and navigating complex international security challenges'.

After bringing about the EU referendum which led to Britain's vote to leave the bloc, Mr Cameron 'will provide an unrivalled perspective on the future of the European Union and Britain's place in the world following Brexit', said the bureau.

Mr Osborne earned more than £500,000 through speeches to Wall Street banks, financial firms and a university in New York during a series of trips in October and November.

In its advice letter to the former PM, Acoba – which vets job offers for ministers and senior civil servants in the period after they leave government – said he could sign up with the bureau three months after his last day in office.

But he must not lobby the Government on its behalf for at least two years, the watchdog added.

He is also not allowed to draw on any privileged information available to him as Prime Minister during his work with the bureau.

Since stepping down as an MP, Mr Cameron has set up a company called the Office of David Cameron Ltd to deal with earnings from activities such as public speaking.

He gave a speech about the political upheavals of 2016 earlier this month at Indiana's DePauw University.