The head of the Ethiopian Orthodox Church, Abune Paulos, has died aged 76, the government has announced.
The foreign ministry said he had been receiving treatment over the past week for an undisclosed illness.
The patriarch’s office is due to hold an emergency meeting on Friday to finalise arrangements for what is expected to be a state funeral.
Abune Paulos led Ethiopia’s 40 million Orthodox Christians – half the population – since 1992.
Mulugeta Aserate Kassa, an adviser at the Ethiopian embassy in London, told the BBC’s Focus on Africa programme the patriarch had been “very healthy” on Wednesday, when he led a service in the Ethiopian capital, Addis Ababa.
He later fell ill and was rushed to hospital, said Mr Mulugeta, a close friend of the patriarch.
The patriarch died early on Thursday morning, he added.
Mr Mulugeta said he could not confirm the cause of death, but the patriarch had suffered from hypertension and diabetes.