By Syed Raza Hassan
ISLAMABAD (Reuters) - Looking to overcome years of mistrust and hostility between their two nations, Pakistan Prime Minister Nawaz Sharif and the new Afghan president, Ashraf Ghani, promised on Saturday to boost security and trade ties.
The two neighbors have accused each other in the past of harboring anti-government Taliban insurgents across their shared border, and bilateral relations were often tempestuous under the previous Afghan president, Hamid Karzai.
But less than two months after taking office, Ghani is paying his first state visit to Pakistan, and the warm words used by himself and Sharif at a joint news conference suggested both sides were making a conscious effort to reset relations.
"We have overcome obstacles of 13 years in three days," said Ghani. "We will not permit the past to destroy the future."
Sharif, who was elected last year in a landslide win, called Ghani a "dear brother" and said the two nations had signed agreements to improve train and road links, increase trade and explore defense, border and energy cooperation.
"Our security and future prosperity remain interlinked," he said. "I ... reaffirmed Pakistan's support for the intra-Afghan reconciliation process that the new government is initiating."
The Afghan government is pursuing peace talks with the Taliban, who have gained ground as NATO pulls back its troops ahead of a full withdrawal.
Kabul is also increasingly turning to regional powers for support, but it will take more than warm words between Sharif and Ghani to repair damaged ties between their countries.
Afghan and U.S. officials have frequently accused Pakistani security services of links to Taliban and Haqqani Network insurgents, who carry out deadly attacks in Afghanistan.
In the past two years, Pakistan has begun leveling the same accusation at Afghanistan, accusing it of tolerating bases belonging to Mullah Fazlullah, the nominal leader of the Pakistani Taliban, a group sworn to overthrow the state.
Diplomats say increased trust and security cooperation is key to tackling the twin insurgencies. But some in the powerful Pakistani security establishment are nervous about Afghanistan's increasingly warm relations with Pakistan's arch rival India.
Many Afghan officials also remain suspicious that Pakistan retains ties to some militants as a counter to Indian influence.
(Writing by Katharine Houreld; Editing by Crispian Balmer)