Chief Palestinian negotiator Saeb Erekat, hospitalised in Israel with Covid-19, has been placed on a ventilator after his condition deteriorated, a spokeswoman for the facility said.

“Mr Erekat had a quiet night but this morning his condition deteriorated, and it is now defined as critical,” a statement from Hadassah spokeswoman Hadar Elboim said.

Erekat was rushed to Jerusalem’s Hadassah Medical Center on Sunday from his home in the occupied West Bank. He contracted the coronavirus on Oct 8.

Erekat, 65, is considered especially vulnerable to the illness because he underwent a lung transplant in the United States in 2017, which suppressed his immune system.