Updated 4.23pm

Former Prime Minister Joseph Muscat has sued lawyer Christian Grima over a claim on Facebook that he “blew up” journalist Daphne Caruana Galizia. 

Announcing the libel suit on Facebook, Muscat said he had no choice to react because Grima had crossed the line with his post. 

Grima made the claim in a post published on May 2, in reaction to a video clip of Muscat's wife Michelle talking about Caruana Galizia's murder. 

In the clip, Michelle Muscat said that she was sorrier about "what happened to her [Daphne]" than the journalist's own family. 

"I told myself 'now I'm going to have to live with her lies'," Michelle Muscat had said in the interview. 

Reacting, Grima wrote on his Facebook page: "Your husband blew her up, Michelle. That's what happened to her."  

Muscat announced the libel suit on Monday, eight days after Grima's post. He dismissed Grima's claim as “totally false”. 

Muscat said that while he believed in freedom of expression and was not a fan libel suits, he had no choice but to react to Grima’s post. 

The former Prime Minister said he could accept criticism, whether it was fair or not. He said he had not reacted when facts had been twisted and speculation used to suit people’s agendas. 

Muscat said however that he could never accept lies such as the ones put across by Grima. 

Grima reacted by saying he would see Muscat in court. 

Caruana Galizia was killed by a car bomb outside her home in October 2017. 

Muscat’s former chief of staff Keith Schembri has since been linked to the murder and the subsequent cover-up. 

Yorgen Fenech, a friend of both Schembri and Muscat, stands accused of ordering the killing. 

On Sunday, Times of Malta reported how Schembri sent Muscat’s security guard Kenneth Camilleri to “calm” murder middleman Melvin Theuma in 2018.