Civil society group Repubblika on Tuesday strongly condemned Parliamentary Secretary Alex Muscat for "lying" when he accused its president-elect Robert Aquilina with threatening parliamentary members on instructions of his brother, Karol, a Nationalist MP. 

During a Public Accounts Committee meeting on Tuesday, Mr Muscat accused Karol Aquilina of sending his brother to threaten MPs during protests last year.

Repubblika said it expected the Prime Minister to openly admonish the Parliamentary Secretary and to stop his deputies from lying and accusing those exercising their fundamental right of expression with threatening them.

"It would seem that the government has learned nothing from the telling-off it received three weeks ago from the Constitutional Court," Repubblika said. 

Mr Muscat, who served in the private secretariat of former Prime Minister Joseph Muscat, continued to insult democracy with his deplorable behaviour, Repubblika said. 

The organisation said it will be requesting the Commissioner for Standards in Public Life to investigate.