Malaysia has said it will not immediately deport 131 Thai Muslims who have fled across the border due to violence in southern Thailand.
Malaysia does not want Thais to start flooding across the border
"The Thai side has asked us whether we can send them back," said Malaysian Foreign Minister Syed Hamid Albar.
But he added: "We cannot just chase people away...There is a need for us to do investigation on our side."
His response is likely to irritate Thailand's leader, who said some of the group were Islamic militants.
Nearly 900 people have died in southern Thailand since the beginning of last year, in violence thought to be fuelled by disenchantment within the predominantly Muslim community.
The mainly Islamic nation of Malaysia has cultural and religious links with Thailand's south.
"We are concerned because we do not want to see the flight of refugees into our countries. It is very difficult for us to handle," Syed Hamid said in unusually candid comments on Friday.
He said he had spoken to Thai Foreign Minister Kantathi Suphamongkhon about reports that the 131 arrivals were afraid to go home because of the violence.
"He has told me there is no truth [in the reports]. I'll be trying to get reports of our own to see what exactly is happening," Syed Hamid said.
But he added that there was "no denying that the situation in Thailand is still not safe, it is still not stable".
He said the Thai government needed to inspire trust among its Muslim people.
"I think the responsibility is for the Thai side to ensure that they can overcome the fear, whether real or perceived fear, in the local community in Thailand, so that they will not come here," he said.
In Bangkok, Thai Prime Minister Thaksin Shinawatra said on Friday that some members of the group who had crossed into Malaysia were Islamic separatists.
"Some of them are militants in disguise. They are trying every possible way to internationalise the unrest issue, but we and the Malaysian government are co-operating closely and there is no problem," he is quoted as saying earlier on Friday.
Controls on the Thai-Malaysia border have been increased in recent days, to prevent further migration across the border.
But according to Malaysian newspaper the New Straits Times, there are rumours that thousands more are expected to cross into Malaysia if the violence in southern Thailand continues.