A German hospital has said that a UN medical worker who was infected with Ebola in Liberia has died despite "intensive medical procedures".

The St Georg hospital in Leipzig said on Tuesday that the 56-year-old man, whose name has not been released, died overnight of the infection. It released no further details.

The man tested positive for Ebola on October 6 and arrived in Leipzig for treatment on October 9 where he was put into a special isolation unit.

Local health officials said last week that the patient was a Sudanese doctor who had arrived in Germany.

Germany has previously treated two other Ebola patients infected in Sierra Leone - a Senegalese expert who was treated in Hamburg and released on October 4, and a Ugandan doctor now being treated in Frankfurt.

The Ebola epidemic has killed more than 4,000 people this year, mostly in Guinea, Sierra Leone and Liberia, and is spread through close contact with bodily fluids.

The US and UN leaders on Monday called for "more robust" international efforts to tackle Ebola after medics in Liberia demanded danger money to treat patients in what officials termed the worst health crisis of modern times.

800 Sierra Leone soldiers quarantined

A batallion of 800 Sierra Leone soldiers awaiting deployment as peacekeepers in Somalia were placed in quarantine after one of its members tested positive for Ebola, military officials said on Tuesday.

They soldiers, who were supposed to join the AU peacekeeping force called AMISOM, are now expected to be subject to a 21-day isolation period.