Pressure grew both within and outside the party for him to quit after the probe into the 2017 auto bomb killing of anti-corruption journalist Daphne Caruana Galizia led to charges yesterday against a prominent businessman with alleged ties to ministers and senior officials.

Party insiders said Muscat would step down once those behind the killing had been charged and his Labour Party had chosen a new leader. Prime Minister Joseph Muscat is under pressure to resign.

Malta's embattled prime minister has received a pledge of confidence from Labor Party lawmakers amid demands for his resignation by citizens angry over alleged links of his former top aide to the auto bomb killing of a Maltese anti-corruption journalist.

Maltese Prime Minister Joseph Muscat, engulfed in crisis over the probe into a murdered journalist, announced on December 1 he planned to step down, saying he would ask his ruling Labour Party to start choosing a new leader for the country next month.

Mr Muscat noted that in addition to three people arrested soon after the bombing for carrying out the actual attack, now there is "someone accused of being the principal person behind this killing".

Fenech, 38, who was until this month chief executive of one of Malta's largest companies, the property-to-energy Tumas Group conglomerate, was taken to court in handcuffs in a police van under a heavy armed police escort nearly two years to the day since three other men were charged with having set off the bomb that killed the journalist on October 16, 2017. Fenech entered pleas of innocence.

Both Mr Schembri and Mr Mizzi have denied any wrongdoing, and Mr Mizzi has denied any business links to Mr Fenech.

Fenech's name was on leaked documents as a source of income for companies named in the Panama Papers, a financial scandal Caruana Galizia was investigating before her death.

Before she was killed, she had alleged that Schembri and Mizzi had been involved in corruption.

Three other men are in custody charged with Caruana Galizia's actual murder, which involved a auto bomb.

Before she died, Caruana Galizia had reported on a money trail and secret companies set up in Panama by Muscat chief of staff Schembri and tourism Minister Mizzi.

"It is not right that a person, with her good and bad, who contributed to democracy had to be killed this way".

A European Parliament delegation is due to arrive on Malta late Monday and stay until Wednesday.

But Muscat himself insisted he would remain in power until the case was "closed".

The Maltese government accepted Theuma's pardon request but later turned down another request for a pardon by Fenech.

Immediately after the hearing, the family of Caruana Galizia urged authorities to continue to probe into who else was involved in the murder. "The situation is desperate", she had written referring to what she unearthed with her digging into suspected widespread corruption in Malta's political and business circles.

Caruana Galizia's family and protesters have taken to the streets and called for Muscat to resign.

A businessman with alleged links to government officials has been charged with complicity in the murder.

Theuma recently was granted immunity from the prosecution in exchange for giving details on who was behind the bombing.

Three people are awaiting trial for Caruana Galizia's murder in a auto bombing but the police investigation is now focusing on who ordered the killing and why.

It was unclear when the photo was taken.