Former British prime minister Tony Blair will step down from his role as the Middle East envoy representing the Quartet -- composed of the United Nations, Russia, European Union and the United States -- next month, the U.N. announced in a statement released Wednesday. Blair served as the prime minister of the U.K. from 1997 to 2007 and has been the Quartet’s envoy to the Middle East since he left Downing Street.

“As the Quartet’s envoy on the ground during the last eight years, Mr. Blair demonstrated an unwavering commitment to the cause of Israeli-Palestinian peace and made lasting contributions to the effort to promote economic growth and improve daily life in the West Bank and Gaza,” the Middle East Quartet said in the statement.

However, during his eight-year term, Blair has been repeatedly criticized for being too close to the Israelis and for failing to do enough to help the revival of the battered Palestinian economy. His departure also comes amid fears of a renewed conflict in the Gaza Strip, which is still recovering from last year’s 50-day war that left more than 2,100 Palestinians and over 70 Israelis dead.

In June last year, before the conflict escalated to a full-blown war, a group of political activists and thinkers had called for Blair’s resignation in an open letter published by the Guardian, highlighting his role during the U.S.-led invasion of Iraq in 2003, which, they alleged, further destabilized the Middle East.

“The occupied Palestinian territories represent another tragic failure of western engagement in the Middle East. … It is our view that, after seven years, Mr Blair’s achievements as envoy are negligible, even within his narrow mandate of promoting Palestinian economic development,” the group wrote in the letter. “We, the undersigned, urge you [the Middle East Quartet] to remove him with immediate effect as a result of his poor performance in the role, and his legacy in the region as a whole.”

Following his departure, Blair will now “concentrate on strengthening relations between Israel and the wider Arab world,” a source close to him, cited by BBC, said. “He will also focus on encouraging Israel to take measures which will dramatically improve the daily lives of Palestinians in Gaza.”