Myanmar on Sunday declared that it will not negotiate with terrorists, rejecting a ceasefire declared by the Arakan Rohingya Salvation Army (ARSA), a Rohingya insurgent group.
Myanmar says its security forces are carrying out clearance operations to defend against ARSA, which the government has declared a terrorist organisation.
The ARSA declared a month-long unilateral ceasefire, starting on Sunday, so that aid could reach to thousands of displaced people in the state of Rakhine, reports Reuters on Sunday.
The impact of ARSA's move is unclear, but it does not appear to have been able to put up significant resistance against the military force unleashed in Rakhine state, where thousands of homes have been burned down and dozens of villages destroyed.
Attacks by militants on police posts and an army base on Aug 25 prompted a military counter-offensive that triggered an exodus of Rohingya to Bangladesh, adding to the hundreds of thousands already there from previous spasms of conflict.
According to the latest estimate by UN workers in the Cox's Bazar region of southern Bangladesh, about 294,000 - many of them sick or wounded - have arrived in just 15 days, putting huge strain on humanitarian agencies' operations.
Thousands of Rohingya remaining in the north-western state of Rakhine have been left without shelter or food, and many are still trying to cross mountains, dense bush and rice fields to reach Bangladesh.