"The leaders are expected to discuss the threat, review ongoing efforts, and explore what more can be done," a spokesman said.

Zardari has hit back at the allegations of double-dealing, arguing that Pakistanis are often the victims of attacks on home soil and that Islamabad is committed to fighting armed groups in the region.

He has vowed to express Islamabad's anger "face to face" when he meets Cameron.

For his part, the prime minister has insisted he stands by his comments.

But Alan Fisher, Al Jazeera's correspondent outside Chequers, said both sides needed to get past the dispute to "frame the ongoing relationship" between the two countries.

"Both sides realise that they need to cool the temperature .. because there has been a war of words over the last week or so."

Zardari under pressure

The British leader's criticism sparked fury in Islamabad, especially as it was made on a visit to India, with which Pakistan has fought three wars since partition in 1947.

The remarks prompted the Pakistani government to summon Britain's ambassador to Islamabad earlier this week for a dressing down.

Zardari came under enormous pressure to cancel his trip over the controversy, but his office insisted that it gives Pakistan a chance to make its case.

Despite standing by his comments, Cameron has accepted that Pakistanis are often the victims of attacks, including the one that killed Zardari's late wife Benazir Bhutto, the former premier assassinated in Pakistan in 2007.

The leaders are also set to discuss the devastating floods in Pakistan which have killed around 1,500 people and affected more than four million.

Zardari's failure to return home immediately in the aftermath of the disaster has drawn criticism from opposition politicians in Pakistan and MPs of Pakistani origin in Britain.

Other issues on the agenda include the war in Afghanistan and how to boost trade between Britain and Pakistan.

The two leaders met for the first time on Thursday since the row erupted, getting together for dinner at Chequers for what sources said would be an informal celebration of Benazir Bhutto.