Civil society group Repubblika is calling for the suspension of Prime Minister Joseph Muscat from the upcoming European Council.

In a letter to the President of the European Council Charles Michel, the NGO,  said it was "unhealthy" to treat the prime minister as "an equal" when "a murder investigation has reached his personal office".

The prime minister's former chief of staff has been questioned twice about the assassination of journalist Daphne Caruana Galizia and released without charge.

“Much as it grieves us to argue for the suspension of Malta’s participation in the European Council it is the firmly held view of Maltese civil society that Joseph Muscat’s participation in the Council risks laundering Joseph Muscat’s reputation at the cost of the democratic viability of the European Union itself,” the organisation said.

It said that “as Maltese and as Europeans we therefore ask you to consider informing Joseph Muscat that he would not be welcome at the upcoming European Council and that you look forward to working with his replacement.”

Dr Muscat is due to attend the European Council on Thursday and Friday along with other European leaders. 

Repubblika, has been organising regular protests calling for the prime minister's immediate resignation over the fallout of the investigation into Ms Caruana Galizia's murder. 

It said it upheld the values of the European Union listed in the Treaty on the European Union and now expected the European Union to “uphold these values with us”.