Philippine officials say action will be taken if the rebels do not leave
The Philippine government has given Muslim rebels 24 hours to vacate towns they are accused of occupying in the country's volatile south.
"Otherwise they shall be forcibly separated from the area," Interior Minister Ronaldo Puno told reporters.
He said about 800 rebels from the Moro Islamic Liberation Front (MILF) had seized several villages.
Christians there have protested against a government-MILF deal that would see a Muslim autonomous zone expanded.
On Monday, the Supreme Court temporarily suspended the deal, following a petition from Christian lawmakers.
Regional tensions have risen since the government and MILF agreed to sign the preliminary accord, which would eventually see the Muslim autonomous zone expanded to include another 712 villages.
Thousands of people in the region protested against the deal this week.
Now Christian leaders in the southern province of North Cotabato have accused the rebels of stealing cattle and burning homes.
"We cannot allow these things to happen," Mr Puno said, saying he was giving the rebels "24 hours to vacate".
But a rebel spokesman, Eid Kabalu, reportedly denied the rebels were occupying land when he spoke to Radio DZBB.
The rebels denied violating the terms of their truce with the government, and express frustration at the slow progress of the peace process.
Monday's court ruling mean the proposed government-rebel deal is now suspended until 15 August, when the government will have to make its case in court.
Under the terms of the proposal, which would be subject to approval in a local plebiscite, the Autonomous Region in Muslim Mindanao (ARMM) would not only be expanded.
It would also have claim to a substantial proportion of the region's rich resources.
Top security and diplomatic officials have played down the threat posed to the delicate peace process by the government's ultimatum.
"This is not a declaration of war, this is normal enforcement of the rule of law," said Hermogenes Esperon, the president's peace adviser, according to the Philippine Daily Inquirer.