Taita Taveta Governor Granton Samboja has left the Opposition coalition, National Super Alliance (NASA) and joined the ruling Jubilee party.
Mr Samboja announced his departure from NASA just moments after presidential candidate Raila Odinga announced that he had quit the presidential race.
The Wiper party point man at the Coast had earlier dismissed claims that he had defected saying that the rumors had come as a surprise to him and accused fellow politicians of propagating the supposed lie.
"I am shocked that some politicians are abusing me behind my back and yet I have not spoken a word. Are they scared of me?" Samboja had posed.
However, the Governor changed tune on Tuesday when he spoke at a Jubilee party rally in Voi.
"I have worked with these two leaders and I am ready to work with them for the sake of development for my people.
"In 2007, we planted and harvested nothing. Same in 2013 and 2017 but we got nothing. This time, we are planting elsewhere where we are assured we will harvest," Samboja declared.
In the run-up to the new declaration, the Governor had been conspicuously absent from NASA rallies at the Coast.
Senator Johnes Mwarume had confirmed to reporters that the Governor had been out of reach and had not responded to invitations to join the campaigns.
"He (Samboja) has remained silent. We wonder why he is no longer interested in supporting the coalition," Mwarume told reporters after a fundraiser in Voi.
Mr Samboja has followed his arch-rival, former Governor John Mruttu who joined the ruling party on Monday.