VATICAN CITY, Feb.28 (Xinhua) -- The resignation of Pope Benedict XVI came into effect at 8 pm local time (1900 GMT) on Thursday, who had left the Vatican by helicopter for the papal vacation retreat in south Rome earlier in the afternoon.

The pope has become the first pontiff to resign in 600 years, after which he is supposed to be addressed as "his holiness" under the title of "Pope Emeritus."

On his last day in office, he pledged to respect and obey his successor, who is set to be elected by cardinals in a conclave next month.

The pope held his final general audience on Wednesday and his last public prayer ceremony last Sunday, both of which drew tens of thousands of Catholic believers and other spectators from across the world.