Former Nationalist general election candidate Hermann Schiavone and television presenters Jean-Claude Micallef and Norman Vella have been called to appear before the PN's Candidates Commission this evening.
The commission, headed by former EU Commissioner Joe Borg, is selecting candidates for the European Parliament elections.
Dr Schiavone was banned by the party from contesting the general election in March, but last May he was elected to the party's executive.
Mr Micallef was initially excluded from being considered as an MEP candidate by the PN because of a pending court case regarding fraud. But in October the court decided he should never have been charged because the issue was a civil and not criminal matter.
Mr Vella made the headlines last month when he was arrested and had his mobile and tablet confiscated for allegedly taking photographs in a restricted area at the airport, where he works. The court found in his favour and threw out the case.