The Party of National Unity (PNU) has denounced it's former national treasurer Peter Kaberia and two others who said they had moved to Meru Governor Kiraitu Murungi's camp.
The three are Mr Kaberia, former governor Peter Munya's running mate in the 2017 election; former Igembe North MP Ntoitha M' Mithiaru; and businessman Kiriinya Nairuti.
They are seen as close allies of Mr Munya, who is now Trade Cabinet Secretary.
Mr Kaberia and Mr M'Mithiaru held a closed-door meeting with Mr Kiraitu on Saturday morning and announced their move in the evening.
The three join several other allies of Mr Munya, including lawyer Mugambi Imanyara and Tigania East MP Josphat Kabeabea, in Mr Kiraitu's camp.
While receiving them, Governor Murungi said he was keen on working with his opponents on the development agenda.
"I am pleased that the top leaders of PNU and strong supporters of the former county government have resolved to throw their support behind me and my administration," he said.
However, the party issued a statement saying the defectors were impostors and that their move had not diminished its strength.
"The PNU [National Executive Council] takes great exception to impostors claiming to hold any office. They have moved out of their own volition and in no way represent PNU," the statement stated.
"What we have seen in Meru are public servants coming out in the open with political rhetoric, contravening clauses and provisions in our Constitution that govern their conduct."
The party said State officers engaging in politics should be fired.
"We urge appointing authorities to take stern disciplinary actions against the individuals."