The Moro Islamic Liberation Front’s (MILF) problem with one of its most hard-line commanders, Ameril Umbra Kato, has raised concerns whether the 11,000-strong group can deliver on any accord that can emerge from its negotiations with the government to settle a bloody decades-long rebellion in the southern Philippines.

Security forces have been on alert amid Kato’s possible breakaway from the main rebel group, which has observed a truce with government troops.

Western countries led by the United States have backed the peace talks, hoping battlefields could become economic growth centers instead of possible breeding grounds for foreign and local extremists.

Rebel chief negotiator Mohagher Iqbal said his group has continued to woo Kato but must decide whether to impose sanctions on Kato and his men if the efforts fail on or before Malaysian-brokered talks with the government resume April 27-28, he said.

“We can’t afford to have a gray area,” Iqbal told The Associated Press. “We told him he has to reply on or before the resumption of the talks.” Rebel spokesman Eid Kabalu said the chances of the talks with Kato succeeding was “admittedly very dim at this time” but the main rebel group has not given up on repairing the first ever-known serious rift among its ranks.

Amid differences with the main rebel group’s armed wing, Kato formed his own group of a few hundred followers, including about 100 armed fighters, a few months ago but suggested he remained under the rebel front. He has opposed talks with the Manila government, saying the negotiations have gone nowhere, Iqbal said.

Government negotiator Marvic Leonen recently said troops have been on alert amid the rebel infighting. The talks would continue despite the problem, he said, but refused to say, however, if the negotiations could bog down if Kato decides to form a new rebel group.

During a resumption of talks in February, Leonen said that he and other officials conveyed their concern to rebel negotiators about Kato. The guerrillas assured him that Kato still belonged to their group.

The Brussels-based International Crisis Group said the problem with Kato was one of several factors that could complicate already difficult negotiations, which stalled in 2008 when a preliminary peace accord fell apart and was later declared unconstitutional by the Supreme Court.

Angered by the non-signing of the accord, Kato and two other commanders attacked Christian communities, killing dozens of civilians, officials said.

Kato’s threat to break away “has raised new questions about the extent of the MILF leadership’s command and control and, thus, its ability ... to deliver on what it negotiates,” the ICG said.

Iqbal played down the problem, saying communist guerrillas and a smaller Muslim rebel group have had similar infighting but those have not halted their peace negotiations with Manila.

No other key commanders have joined Kato, but Iqbal said his group recently found out that “less than 10 low-level commanders” have joined the disgruntled rebel leader.