El-GENEINA, Sudan, Feb 12 (Reuters) - Sudan condemned a threat by neighbouring Chad on Tuesday to expel around 250,000 Darfuri refugees who have fled to Chad's eastern deserts because of a five-year conflict in Sudan's west.

Chad's prime minister said on Monday the refugee situation was sowing insecurity and raising tension between Chad and Sudan. He called on the international community to relocate them and threatened to expel them if it did not.

"The Chadian announcement violates the laws and charters of the United Nations High Commission for Refugees," Mohamed Ahmed al-Aghbash, Sudan's Commissioner of Refugees told state news agency SUNA.

He said Chad was using the refugees as a bargaining chip with Sudan. Both countries have traded accusations that they are each supporting rebel groups revolting against the other's central government.

Chadian President Idriss Deby was besieged in his palace this month by rebels he said included Sudanese forces, and Khartoum says Chad is directly helping Darfur rebels, especially the Justice and Equality Movement (JEM).

Many of JEM's leaders are from Deby's Zaghawa tribe. JEM leader Khalil Ibrahim implored Chad to be patient and thanked Deby for hosting the Darfur refugees for so many years.

"If the Sudan government stopped supporting the Chadian rebels there will be no problem," he said. "As long as Sudan is trying to change the government in Chad, this is a normal response for the Chadians to say this."

After a government offensive to retake control of three West Darfur towns last week, another 12,000 Darfuris joined the 240,000 refugees already in camps in eastern Chad. The U.N. refugee agency (UNHCR) said it expected many more to arrive. (Reporting by Opheera McDoom; Editing by Michael Winfrey)

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