Updated 11.50am with new video
Godfrey Farrugia submitted his nomination to contest the general election under the Partit Demokratiku banner, just hours after quit the Labour Party and accused it of having had lost its soul.
The former health minister will, therefore, stand for the same party headed by his partner Marlene Farrugia, which forms part of the Nationalist Party coalition against Labour.
He submittted his nomination at 10.15am, shortly after he posted on his Facebook page a letter he sent to the PL president saying that he was quitting "with immediate effect".
He told reporters that tomorrow he will be addressing the Nationalist Party's mass meeting in Żebbuġ. He later headed towards the PN headquarters where he was given a warm welcome.
Dr Farrugia will be contesting the sixth and seventh districts. The popular family doctor was elected on the seventh electoral district in 2013 after drawing 2,089 first count votes.
After submitting the nomination, the Farrugia couple and other PD officials headed to the PL headquarters in Ħamrun and to PBS to protest at the way the former minister's nomination had been almost ignored.
Dr Farrugia said he is stepping down from all Labour structures because he felt the party had retained its name but lost its soul.
The former Labour Health Minister and whip cited a quote from Guże Ellul Mercer to justify his decision: "I'm in the workers' party because it is built on noble principles: it believes that a human being should live as a human being, work as and feed himself as a human being... whether he's been born into a rich or poor family."
He quit the post of party whip two weeks ago after writing the Prime Minister a strongly-worded open letter, saying that while he considered himself a Labourite "I do not feel I belong there."
Speculation about his political future have been mounting after Marlene Farrugia, also a former Labour MP, set up her own party, and will be contesting the June 3 election under the Nationalist Party coalition umbrella.
Asked about Dr Farrugia's resignation, Prime Minister Joseph Muscat curtly said: "I wish him luck for the future. I respect Godfrey personally".
In a tweet, Nationalist Party leader Simon Busuttil welcomed Dr Farrugia into the coalition and said more people are standing up to be counted.