People's Trust Party leader John Katuku has criticised former Makueni governor Kivutha Kibwana for leaving the Azimio coalition for Kenya Kwanza.
Katuku termed Kibwana's move on Tuesday uncalled for and unfortunate.
"It's now clear Prof Kibwana and company were not in Azimio for believing it but for political survival. Very unfortunate," he said in a statement.
Katuku urged other Azimio members not to be swayed by the actions of defectors and remain faithful to Azimio and its ideals.
"I urge all those who belief in true democracy, fair and just society to remain put in Azimio. Change is coming home very soon through Raila Amolo Odinga and Martha Karua," he said.
Kibwana on Tuesday decamped to President-elect William Ruto's side, days after poking holes in the issues Azimio are banking on to overturn Ruto's win.
The former governor was welcomed in the Kenya Kwanza camp by Ruto at his Karen home.
Ruto said Kibwana will join his legal team in the presidential petitions filed against his victory.
"We associate with the leadership that Prof. Kibwana has manifested in agreeing to work with us in furthering our country’s development agenda," Ruto said in a tweet.
Kibwana had served Makueni residents for two terms as the governor and launched his senatorial bid to replace Mutula Kilonzo.
He flopped at the polls after he lost to Wiper party's Dan Maanzo.