Businessman Yorgen Fenech is telling police Keith Schembri was behind murder, sources say
His lawyers did not respond to a request for comment.
Muscat said he would only comment “once investigations are over, hopefully in a few hours”.
She was killed when her rental car exploded near her home in the village of Bidnija in October 2017.
He is understood to have claimed to police Schembri approached him about Caruana Galizia in November 2016.
Last Satrdy Fenech was given a temporary reprieve from questioning when he was admitted to hospital with chest pain
He was arrested last week after trying to leave Malta on board his yacht.