Robert Cutajar is expected to be appointed the new whip of the Nationalist Party group in parliament.
He will take over from David Agius, who has been elected party deputy leader for parliamentary affairs.
Mr Cutajar, a former mayor of Mellieħa, was nominated by party leader Adrian Delia, PN sources said.
The role of the party whip is to enforce party discipline in parliament. Whips ensure that MPs are present in the House and schedule their speaking time. They also ensure that MPs vote according to party policy.