A two-day summit of Pakistan, Afghanistan and Iran begins here on Friday to advance efforts for enhancing mutual cooperation and establishing peace and security in the region.

Afghan President Hamid Karzai arrived Islamabad on Thursday while Iranian President Mahmoud Ahmadinejad also arrived separately for the two-day summit being hosted by President Asif Ali Zardari in Islamabad.

The three presidents are due to conduct two sessions.

On Wednesday, Ahmadinejad unveiled new strides in its nuclear programme in a defiant blow to US and EU sanctions designed to rein in its atomic activities.

"I don't think so," a senior Pakistani government official told AFP when asked if mounting tensions between Iran and Israel, and the showdown over Iran's nuclear programme, would dominate the summit.

"The trilateral summit will discuss cooperation on counter-terrorism and transnational organised crime including drug and human trafficking and border management," the official said.

The talks also come with stepped up efforts to kickstart peace talks with the Taliban designed to end 10 years of war in Afghanistan