KIEV (AFP) - Pro-Russian insurgents in Ukraine's eastern separatist Donetsk region said Friday (Oct 23) they had banned Doctors Without Borders (MSF) and UN agencies, in a move the medical charity described as worrying.

MSF provides crucial medical care for patients in the area, especially those suffering from diabetes and kidney failure, as well as operating an anti-tuberculosis programme in Donetsk's prisons.

In late September, the Geneva-based MSF and nine other non-governmental relief groups were kicked out of the neighbouring rebel province of Lugansk.

At the time, the Donetsk militia leaders were more restrained, saying that they were checking various organisations' registration papers and right to import various drugs.

But on Friday, a representative of the self-proclaimed Donetsk People's Republic said they had decided to follow suit.

"I can confirm the decision to strip its (MSF's) accreditation," the unnamed official told AFP by phone.

Friday's decision was due to unspecified legal violations, the official said, adding "we reserve the right not to divulge the reasons".

The official said the International Committee of the Red Cross and the Czech Republic's People in Need - two other earlier targets of alleged violations - would still be allowed to operate.

But UN agencies such as the World Food Programme would be affected by the ban as they did not have the necessary accreditation.

The WFP would still be able to carry out some of its functions through the People in Need group, however, the official said.

MSF director of operations Bart Janssens warned that the ban would have an impact on public health and said the group had asked Donetsk's authorities to reconsider.

"We are extremely worried. MSF is the largest player in the region and now we will have to stop people's treatment," Janssens told AFP by telephone.

"This is a dramatic decision," he said.

The United Nations estimates that the 18-month conflict in Ukraine's industrial heartland has claimed the lives of at least 8,000 people and injured around 18,000 - most of them civilians.

The separatists rely on medical and other support from Russia, which denies instigating or backing the insurgency in reprisal for last year's ouster of a Moscow-backed leadership in Kiev.

The pro-Moscow militias treat Western groups with extreme caution, suspecting some of being EU and US spies.