England 2018 bid chiefs fear the programme will cause a backlash among the 22 FIFA members who will vote on the World Cup hosts - a number have already been asked to respond to allegations by the BBC programme.

Cameron, who will spend three days in Zurich next week trying to win over FIFA, said he had already spoken to some executive committee members about the issue.

The Prime Minister said in an interview with the BBC's Football Focus to be shown tomorrow: "Is it frustrating that Panorama's doing this programme a few days before? Of course it is.

"But it's a free country and you have to roll with that. I think FIFA will understand that and I think we also have to try and convince them that, yes we've got a robust and independent media, but our media love football and when it comes to the World Cup in terms of audience, in terms of the press coverage around the world, actually the media will give it a fantastic boost here in this country."

Cameron said he and bid leaders would try to focus FIFA members' minds on the technical merits of England's campaign.

He added: "I think the job that Andy Anson and others and myself are going to have in Zurich is to say to FIFA, let's look at the bids on their merits, look at the technical aspects, look at the stadia, look at the fans, look at the country, look at what England can offer and yes of course we have a free media, a democracy, but look at the upsides and the advantages and we just have to make that case."

One of the targets of Panorama's investigation is FIFA vice-president Jack Warner, the Trinidadian government minister who has been the subject of programmes in the past.

Earlier this week Warner told the Press Association that Panorama appeared to be deliberately undermining England's bid and he has now returned to the attack.

He told Trinidad newspaper Newsday: "I think they [Panorama] have a death-wish for the English FA and I hope they fail because it isn't too correct what they're trying to do."

Warner remains the most crucial vote for England to capture as he and fellow CONCACAF delegates Chuck Blazer and Rafael Salguero are likely to vote the same way, though there is some suggestion that Salguero may follow his heritage and vote for Spain/Portugal.

The importance of Warner to England's chances explains why Cameron has invited him to lunch in Zurich next week, most likely on Tuesday just hours after Panorama has been screened.

Warner insisted his final decision had still to be made.

He said. "We have not decided how we're voting in the CONCACAF. I know that, in some ways, our votes are key to what's happening.

On Monday, I'll meet my team and then we shall decide."

Warner also praised a two-day FA/Premier League media workshop, which has been taking place in Trinidad this week as "one of the best things to ever happen to football in the region".

Meanwhile, Russia have still to confirm whether their prime minister Vladimir Putin will travel to Zurich to back their campaign.

Putin's travel plans are usually only announced at the last minute for security reasons but it is widely expected he will go for the vote. Russia's bid leader, Alexei Sorokin, said: "There will be plenty of colourful figures, including business representatives and footballers."

Arsenal player Andrei Arshavin and Russian pole vaulter Yelena Isinbayeva have confirmed their participation.

Holland/Belgium are also bidding for 2018 and FIFA will vote on the hosts on December 2.