COTABATO - Philippine Muslim rebels on Wednesday angrily rejected accusations they were behind the abduction of an elderly Irish priest and threatened to stop helping in the search for him.

Chief peace negotiator for the Moro Islamic Liberation Front (MILF) said the accusations over the kidnapping of Father Michael Sinnott, 79, were unacceptable and could affect pending peace talks with the government.

"We are now reaching to our counterparts in the government to stop all these accusations," Mohagher Iqbal told reporters after Interior Secretary Ronaldo Puno blamed the MILF for the Irishman's abduction.

"If Puno does not stop, we are considering stopping our help to the rescue effort."

On Tuesday, officials said intelligence reports pointed to rogue MILF elements as being behind the October 11 kidnapping of Sinnott, a Roman Catholic missionary based in the southern city of Pagadian.

The MILF have targeted foreign missionaries in the south in the past. In a video released by the unknown kidnappers last weekend, the priest relayed a $2-million ransom demand which the authorities and his religious order both promptly rejected.

Meanwhile, two police companies have deployed to the Lanao region of the southern island of Mindanao to look for Sinnott, a police statement said.

Other police units have deployed to surrounding areas to prevent the kidnappers fleeing with their hostage, reinforcing military units already in the area, police said.

In the Philippines, a company traditionally consists of about 100 men. "We already have forces on stand-by in the area but we are adding more forces considering the credible reports that they are in that area," said Allan Molde, spokesman of a committee working for Sinnott's release.

Sinnott, who has a history of heart problems, was kidnapped at the Society of Saint Columban mission house in the Mindanao city of Pagadian. Government officials earlier said that efforts to revive peace talks with the MILF could be affected by the allegations that MILF members were involved in the abduction.

The negotiations stalled last year when two MILF commanders broke a five-year ceasefire and launched large-scale attacks across Mindanao, but both sides have since agreed to resume peace talks this year.