The Opposition said it was "incredible" that Joseph Muscat - the man who began his career campaigning to keep Malta out of the EU and ended it with getting the island greylisted - still blamed the Nationalist Party "for all his bitter failings". 

The party was reacting to comments that the former prime minister gave to Times of Malta in an interview.

In the first part of the interview, published on Friday, Muscat repeatedly blamed the Opposition for several of the problems facing the country, saying the PN had failed to back up the government when national unity was required.

In a statement on social media, the PN said Muscat's interview is "a desperate attempt to assert his dominance over Robert Abela" and keep the PL from expelling him over his "involvement in creating a culture of impunity that led to the barbaric assassination of a journalist". 

"While the official Prime Minister hides from interviews, Muscat threatens to return to politics if people keep annoying him. This shows exactly what Muscat thinks of his crowned continuity candidate, what he thinks of the electorate and how he views the purpose of politics," the party added. 

The second part of the interview dealing with corruption and Daphne Caruana Galizia's murder will be published on Sunday. 

Arnold Cassola: Get ready to re-enter politics

Reacting to comments by Muscat, who said he did not rule out a return to politics, independent candidate Arnold Cassola challenged the former premier to get ready to re-enter the political scene. 

Asked if he mulled a return to Maltese politics, in the interview Muscat said he did not exclude a return "if they keep annoying me".

In his reaction, Cassola warned Muscat that "until justice is served for all your misdeeds, rest assured I will annoy you... and how".