Ageing Muslim rebel leaders in the southern Philippines are voicing growing frustration that efforts to end one of Asia's longest and deadliest insurgencies have hit a diplomatic brick wall.
Moro Islamic Liberation Front chairman Murad Ebrahim expressed hope after an historic meeting with Philippine President Benigno Aquino in August that peace talks were on a "fast-track" and a final deal was within sight.
But negotiations stalled soon after when the government offered its roadmap for peace, a document Murad called an "exercise in futility" and said could lead to reigniting a conflict that has claimed an estimated 150,000 lives.
"There is an impression that it is even heaven and earth," Murad told reporters recently at the MILF's rural Camp Darapanan headquarters in the rural southern Philippines, in reference to the two sides' positions.
Murad insisted there would be no more direct talks between two sides' peace panels until the government produced a more realistic and workable blueprint, however the government has rejected the MILF's demand.
The stalemate is the latest setback to 10 years of talks that some observers say are inevitably doomed because the national government will not be able to meet the MILF's core requirement of an autonomous substate in the south.
There are roughly four million Muslims in the southern Philippine region of Mindanao, an area they see as their ancestral homeland dating back to Islamic sultanates established long before Spanish Christians arrived in the 1500s.
The region is among the most fertile and resource-rich in the Philippines, but it is also one of the country's poorest and undeveloped, a legacy of the conflict that began four decades ago.
Muslims, known as Bangsamoro, are now a minority in Mindanao but insist they should be allowed to largely govern the region themselves and control its potential riches.
"We feel we are colonised," Murad said.
The MILF, the largest Muslim rebel group with about 12,000 soldiers, has for the past decade sought to negotiate a settlement rather than achieve its aims through armed insurgency, which peaked in the 1970s when an all-out war raged.
However negotiations have gone virtually nowhere since 2008 when the Supreme Court blocked a peace deal that would have opened the door to an autonomous Muslim substate, ruling it was "unconstitutional".
President Benigno Aquino, who came to power last year, promised to reinvigorate the peace process and invested much personal capital by meeting Murad in August.
Their encounter in Japan was the first ever face-to-face talks between a sitting Philippine president and MILF leader.
However the optimism within the MILF faded after the government put forward its peace plan a few weeks later with the explicit condition that it will only work within the constitution, effectively ruling out a substate.
At this stage, Aquino is unwilling to invest further political capital by lobbying parliament to change the constitution for what many among the majority Catholic population would oppose, security analyst Rommel Banlaoi told AFP.
"Right now there is a huge gap in misunderstanding," Banlaoi, head of the Philippine Institute for Peace, Violence and Terrorism, said after he met with Murad.
"The Philippine government insists on using the constitutional framework to address the Bangsamoro problem. But the Moro Islamic Liberation Front is insisting that what they want is a substate."
The government is instead offering the MILF "enhanced autonomy" as part of a self-coined "three-for-one" plan that also involves economic development and government recognition of the Bangsamoros' historical ties to the land.
Chief government negotiator Marvic Leonen has maintained in recent weeks that the two sides in fact have many positions in common and a peace deal is achievable before Aquino's term ends in 2016.
"There are many sources for optimism," Leonen told AFP, although he conceded there was still no date yet for when the two sides would resume negotiations.
Murad, who is in his early 60s, and other ageing rebel leaders, say they are desperate to sign a peace deal before they have to give way to a younger generation that has the potential to be far more militant.
"We need to put in place a viable political solution that will entice the next generation to toe the line of the peace process," said Murad, a fluent English speaker who went to a Catholic university before joining the rebellion.
"The younger generation can be more more inclined to violence because most were born during the war."