President Barack Obama and Pakistani Prime Minister Nawaz Sharif on Thursday issued a joint call for the Taliban to return to peace negotiations with the Afghan government.

Obama and Sharif "called on Taliban leaders to enter into direct talks with Kabul and work toward a sustainable peace settlement," according to a joint statement, following a meeting at the White House.

The US sees Pakistan as one of the few with influence over the extremists. The new Taliban leader Akhtar Mansour is believed to have close ties to Islamabad.

But some in Washington believe Pakistan has not done enough to bring its influence to bear and to persuade the group to renounce violence.

Obama recently announced that US troops would be staying in Afghanistan longer than he had promised, but few believe a military solution is possible.

The White House is keen to get the Taliban back to the negotiating table, after a first round of talks led to a dead end.

The resurgent Islamists briefly captured a key northern Afghan city this month.

Kabul has accused Islamabad of harboring and nurturing Taliban insurgents -- allowing them to launch attacks in Afghanistan before melting back across the border.

Obama recently previewed his meeting with Sharif by saying, "I will continue to urge all parties in the region to press the Taliban to return to peace talks and to do their part in pursuit of the peace that Afghans deserve."