Afghan efforts to broker peace with the Taliban enter a new phase this week with the first scheduled visit of envoys to Islamabad, part of a growing recognition that the process hinges on Pakistan.
Afghanistan's ex-president Burhanuddin Rabbani takes a group from President Hamid Karzai's High Council for Peace to neighbouring Pakistan on Tuesday for talks with President Asif Ali Zardari and Prime Minister Yousuf Raza Gilani.
Pakistan is increasingly seen as key to Afghan stability, despite historic tensions between the two countries linked to Pakistan's desire to extend its sphere of influence in the region as a bulwark against arch-rival India.
Key Taliban figures are believed to be hiding out in Pakistan's wild border regions, while experts say agents from its powerful Inter-Services Intelligence (ISI) have protected or even controlled the militants for years.
Islamabad has said it stands ready to facilitate dialogue between Afghanistan and the Taliban.
"There will be talks with all stakeholders about bringing peace to Afghanistan," Rabbani's deputy Ataullah Ludin said, speaking about the three-day visit.
"This trip is the beginning. We cannot talk about the result now, however, we are optimistic for all peace efforts."
The move comes at the start of a crucial year for Afghanistan - limited international troop withdrawals are expected to start in July before a planned handover of responsibility for security to Afghan troops in 2014.
But some international diplomats and commanders enter 2011 convinced that the plan can only succeed if there are meaningful talks with the Taliban, and the role of Pakistan is seen as crucial.
Taliban leaders fled to Pakistan's border regions after the 2001 US-led invasion of Afghanistan after the September 11 attacks.
Most of the Taliban's top command, including supreme leader Mullah Omar, are believed to be hiding in Pakistan, mostly in the southwestern city of Quetta.
The militia is "intellectually and politically independent but physically under the control of Pakistan", said Gilles Dorronsoro, a visiting scholar on Afghanistan at the Carnegie Endowment for International Peace. According to Mullah Arsala Rahmani, a former Taliban mediator in Kabul, "at least 29 important Taliban leaders have been arrested by the ISI" since 2001.
Relations between Afghanistan and Pakistan have long been tense, but the intensity of the rhetoric between them has eased since Zardari took over from Pervez Musharraf in 2008.
It seems that Afghanistan may need all the help it can get in making progress on peace.
Karzai made negotiations a top priority in 2010, calling a national conference and creating the High Council for Peace. But attempts to open discussions with the rebels have so far got nowhere.
Media reports in November suggested a Pakistani shopkeeper posing as a senior Taliban leader was brought to Kabul for talks with Karzai before being exposed as a fake. Afghan officials deny he was ever brought to the capital.
Another major setback was Pakistan's arrest last February of Abdul Ghani Baradar, described by the US as Mullah Omar's right-hand man who was rumored to be exploring peace contacts.
By detaining him, "Pakistan was telling Kabul, the West and other Taliban leaders that nothing can happen without it", Dorronsoro said.
In public, too, Islamabad has made clear that it believes it is crucial to bringing peace to Afghanistan.
"Nothing will happen without us, because we are a part of the solution," said Gilani in October, reiterating that his government was ready to facilitate dialogue between Kabul and the Taliban.
Last week, foreign affairs ministry spokesman Abdul Basit confirmed the High Council for Peace's visit and vowed Pakistan would "continue to support and help in whatever way the Afghanistan government wants".
Experts say that one key to getting Pakistan to play straight is for the United States to be flexible when it comes to Islamabad's main obsession - India's growing influence in Afghanistan and Washington.
But any policy seen as soft on terror could jeopardize President Barack Obama's re-election prospects in 2012, a date that Dorronsoro warns could become "a real problem".