Papua New Guinea's Housing Minister Justin Tkatchenko has left the People's National Congress (PNC) party of former prime minister Peter O'Neill.
Mr Tkatchenko, who is also the MP for Moresby South, issued a statement to confirm he was leaving the PNC.
He said he was re-joining the Social Democratic Party led by his close ally, Powes Parkop, the National Capital District governor.
Mr Tkatchenko entered Parliament under the Social Democrat banner in 2012.
But he and many other MPs soon joined Mr O'Neill's party, which dominated Parliament for seven years.
The minister's move is the latest in a series of defections from the former ruling party, since Mr O'Neill was replaced as prime minister by James Marape in May.
Mr Marape, who was also a member of the PNC, now heads the Pangu Pati which has become the biggest party in Parliament.