Pakistan President Asif Ali Zardari will visit Iran on Tuesday for two days of talks with Iranian leaders on Afghanistan and ways to boost economic ties, the foreign ministry said.
It will be Zardari's first visit to neighbouring Iran since taking office last September.
"President Zardari will meet top Iranian leaders on Tuesday and on Wednesday he will attend the summit of the Economic Cooperation Organization (ECO)," foreign office spokesman Abdul Basit told AFP.
Talks between Zardari and Iranian President Mahmoud Ahmadinejad will focus on regional and global issues, including the situation in war-torn, neighbouring Afghanistan, the spokesman said.
"The talks will also focus on the 7.5-billion-dollar project to transport Iranian gas," Basit said. "It is Pakistan's effort to use the visit to further boost economic and trade ties between the two countries."
The 2,600-kilometre (1,615-mile) pipeline, to carry gas from Iran to Pakistan and India, was first mooted in 1994 but has been delayed by repeated disputes over prices and transit fees.
Pakistan and Iran agreed last October to start the project without India after fresh disagreements between New Delhi and Tehran.
The ECO summit will focus on how the organisation, formed in 1985 by Iran, Pakistan and Turkey, can deal with the world financial crisis.
The presidents of Afghanistan, Azerbaijan, Tajikistan and Turkey, along with the heads of other countries in the region, are also to attend the summit.
The International Monetary Fund is propping up the Pakistan economy and last November approved a stand-by loan of 7.6 billion dollars to stave off a looming balance-of-payments crisis.
The United States, a key Pakistan ally, has said Iran would be invited for an international conference later this month to define a better way to foster reconstruction and democracy in Afghanistan and halt the Taliban insurgency.
Tehran officials are considering the invitation, saying the problems plaguing their war-torn neighbour cannot be solved without their involvement.