The Prime Minister's office in Papua New Guinea says Sir Michael Somare has resumed office following legal advice, and there's no concern about the stability of the government.
Sir Michael voluntarily stepped aside as Prime Minister in December to allow for a tribunal to be set up to investigate charges of misconduct in office.
Sam Abal was named acting prime minister in his place.
But the media advisor to the Prime Minister's office, Betha Somare says Sir Michael has since received advice that he could not legally step aside ahead of a tribunal, and he's now resumed his duties after taking five weeks leave.
She says he will now continue with his prime ministerial and electoral duties until he is legally obliged to step down
"It hasn't begun yet and until the Chief Justice indicates that he is going to set up a tribunal, then obviously the PM will have to step down, step aside once a tribunal has been set up."
Betha Somare Sam Abal is now deputy Prime Minister and is comfortable with Sir Michael's decision.