Putin was born in Leningrad (now Saint Petersburg) and studied law at Leningrad State University, graduating in 1975. Putin worked as a KGB foreign intelligence officer for 16 years, rising to the rank of Lieutenant Colonel, before resigning in 1991 to begin a political career in Saint Petersburg. He later moved to Moscow in 1996 to join the administration of President Boris Yeltsin. He briefly served as Director of the Federal Security Service (FSB) and Secretary of the Security Council, before being appointed as prime minister in August 1999. After the resignation of Yeltsin, Putin became acting president, and less than four months later was elected outright to his first term as president and was reelected in 2004. As he was then constitutionally limited to two consecutive terms as president, Putin chose to become the prime minister again from 2008 to 2012, and was reelected as president in 2012, and again in 2018. In April 2021, following a referendum, he signed into law a constitutional change that would allow him to run for reelection twice more, potentially extending his presidency to 2036.