After the PF won the 2011 election, Lungu became Junior Minister in the Vice-President's office. He was subsequently promoted to Minister of Home Affairs on 9 July 2012. He became Minister of Defence on 24 December 2013 after Geoffrey Bwalya Mwamba resigned from his ministerial post, and he functioned as Acting President during President Sata's long term illness in 2013–14. 