Chief Palestinian negotiator Saeb Erekat speaks to reporters in Ramallah, in the Israeli-occupied West Bank, on July 1, 2019. (Mohamad Torokman/Reuters)

JERUSALEM — Saeb Erekat, a top Palestinian leader who tested positive for the novel coronavirus this month, was placed on a ventilator Monday and is in critical condition at an Israeli hospital, the facility said in a statement.

Erekat, well known to diplomats as the Palestinians’ chief negotiator and the leader most frequently quoted by Western media, was rushed from his West Bank home to a hospital in Tel Aviv on Sunday, then transferred to Jerusalem’s Hadassah Ein Kerem Medical Center.

The 65-year-old has a history of respiratory illness and underwent a lung transplant in 2017. Erekat is also fighting a bacterial infection, the hospital said.

His daughter tweeted late Sunday that her father was stable in a coronary care unit, where he was receiving high flows of oxygen. But his condition worsened overnight, the hospital said.

“His situation is not good,” his brother told Agence France-Presse.

Erekat was not the only high-profile Palestinian leader to contract the virus in recent weeks. Longtime activist and official Hanan Ashrawi tested positive for the coronavirus Oct. 11.

Erekat has played a central role in Palestinian politics and diplomacy for decades. Since the early 1990s, he has been a high-ranking member of or led negotiating teams in Madrid, Oslo and Washington and at Camp David in Maryland.

Since 2015, Erekat has been the secretary general of the Palestine Liberation Organization Executive Committee. A member of the ruling Fatah party and a committed proponent of an independent Palestinian state, he is considered one of Palestinian Authority President Mahmoud Abbas’s closest allies.

“Saeb Erekat has been the central figure in Palestinian negotiations with Israel, or in decisions to stay out of such negotiations, for over two decades,” said Dan Shapiro, former U.S. ambassador to Israel. “Outside of Palestinian Authority President Mahmoud Abbas himself, there is no one who has had such influence on these decisions.”

Erekat was diagnosed with pulmonary fibrosis and traveled to the United States for a lung transplant three years ago. He made a nearly complete recovery and maintained a full professional schedule afterward.

“I feel as good as I’ve ever felt,” he told a Washington Post reporter during a 2019 interview in Jericho, his hometown. Erekat spent the first weeks of his illness at his family home there.

The West Bank has seen more than 4,200 positive cases of the coronavirus, with an estimated death toll of more than 350. Unlike neighboring Israel, the Palestinian Authority declined to impose a second general lockdown; infections in the territory began to climb after restrictions were lifted following the Ramadan holidays.

Palestinian officials have said they are hamstrung in clamping down on transmission of the virus because of the thousands of workers who cross back and forth to Israel every day.

In recent months, Erekat has been central to a pitched battle of wills between the Palestinian leadership and the government of Israeli Prime Minister Benjamin Netanyahu. In response to Netanyahu’s avowed plans to annex Jewish settlements in the West Bank, the Palestinian Authority cut off long-standing cooperation with Israel on security and financial issues.

The loss of tax transfers has sparked a financial crisis in the territories, but the leadership refused to budge even after Netanyahu shelved annexation plans as part of a diplomatic accord with the United Arab Emirates.

Some Arab states hailed that deal as a breakthrough, but Erekat and Abbas doubled down on their decades-long insistence that no agreements should be signed until Israel withdraws from the West Bank and recognizes a Palestinian state.

“The question today is not about hardship for Palestinians,” Erekat said at the time. “We have had hardship all our lives. We need to finish this. We need our independence. We need our freedom.”

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