Can Cameron deliver on anti-corruption pledge?

David Cameron has been praised for taking on the issues of corruption and tax transparency but pressure groups are warning he must put his own house in order first, writes Naomi Grimley.

The prime minister has ensured his anti-corruption summit this week has already started generating headlines following his apparently unguarded remarks to the Queen that the leaders of some "fantastically corrupt" countries - Nigeria and Afghanistan - will be attending.

Leaving aside the inevitable questions about his diplomatic skills, this is perhaps a good moment to take a look at a subject that has become close to his heart since he took office.

Indeed, if it had not been for the inconvenient fact that details of his late father's business affairs appeared in the cache of documents leaked from the law firm Mossack Fonseca, David Cameron could have taken some satisfaction at the revelations in the so-called Panama Papers last month.

• Panama Papers: In-depth report

• Who's been caught in the scandal?

• Ten things we've learned

• How assets are hidden and taxes dodged

After all, it was a good 10 months ago that he got to his feet in Singapore to argue that the more secretive parts of the world's financial system needed to be reformed. He told his audience about his own fears that ill-gotten gains were being stashed away in London without proper scrutiny.

"With £122bn of property in England and Wales owned by offshore companies, we know that some high-value properties - particularly in London - are being bought by people overseas through anonymous shell companies, some of them with plundered or laundered cash," he admitted.

Thursday's summit is the first of its kind for years. Guests will include US Secretary of State John Kerry and the President of Nigeria, Muhammadu Buhari.

Muhammadu Buhari and John Kerry will be two of the summit's most high-profile attendees

Anti-Corruption Summit: London 2016

On Thursday, 12 May, David Cameron will host an international anti-corruption summit - the first of its kind. Political leaders, businesses, sporting organisations and charities will meet at Lancaster House. The government says the summit aims to agree a package of practical steps to:

• expose corruption so there is nowhere to hide

• punish the perpetrators and support those affected by corruption

• drive out the culture of corruption wherever it exists

Cameron pledges to tackle corruption

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It has been in the pipeline for a while, which is why Dame Margaret Hodge was one of the opposition MPs who praised the prime minister's "leadership" on the issue in a special Commons debate last week. But she, like many transparency campaigners, is worried whether anything concrete will come out of this gathering.

Dame Margaret Hodge welcomed the government's commitment to tackling corruption but said it needs to take serious action

The prime minister was converted to the cause of tackling corruption by the man he calls his global "guru", Prof Paul Collier from Oxford University.

Prof Collier has long insisted that a lack of transparency holds back developing countries by stunting their tax base and repelling new business. He's used the rather colourful analogy of anonymous shell companies - set up in tax havens - being like "getaway cars" for the world's criminal and corrupt.

Next month, Britain itself will bring in a new public register of beneficial ownership - meaning that anybody will soon be able to see who really owns each company in the UK. David Cameron argues only about three other countries in the world have bothered to do this and he is proud of the achievement.

The big problem for the prime minister is that the British overseas territories are not going as far as he would like in their transparency. Crucially, their registers will not be public ones - rather, they will be private and only available to law enforcement agencies in the UK.

British overseas territories such as the Cayman Islands have come under fire in the wake of the Panama Papers

The Panama Papers scandal has thrown the issue into sharp relief because more than half of the offshore companies featured in the released documents were, in fact, registered in UK overseas territories like the British Virgin Islands. Transparency International calls it the "Achilles heel" in the prime minister's crusade.

Last month, the Premier of the Cayman Islands, Alden McLaughlin, argued that any register in his jurisdiction "certainly will not be available publicly or available directly by any UK or non-Cayman Islands agency".

Jeremy Corbyn has questioned whether the prime minister can declare his anti-corruption plans a success if the Cayman Islands are "celebrating" in this way.

Already, the heat is being turned up on Mr Cameron from other quarters too. A group of 300 economists this week demanded that the "veil of secrecy" surrounding tax havens should be lifted.

Thomas Piketty, author of Capital in the Twenty-First Century, is among the 300 economists urging world leaders to lift the veil of secrecy surrounding tax havens

A collection of Nigerian civil society groups has also sent a pointed letter to Number 10. It read: "It is ironic that the countries that pride themselves on their own lack of corruption are the very ones providing most of the corruption services to our corrupt officials."

Sarah Chayes, author of a book on global corruption called Thieves of State, still insists Mr Cameron has shown courage for holding the conference at all.

"There was no way he could have convened a summit about the issue of corruption in London without the particular role of the London property market, the City, and British overseas territories in servicing this type of corruption being highlighted. That way, you were guaranteed to put yourself under the spotlight," she told me.

But compliments about his courage could turn into accusations of hypocrisy if David Cameron is not able to persuade the overseas territories to do more on transparency.

Many non-governmental organisations (NGOs) believe that when David Cameron leaves office he will make this issue a major theme of his post-premiership years. A lot could ride, then, on whether this summit can deliver the change the prime minister himself wants to see.