Mike Sonko (L) poses for a picture with DP William Ruto on July 30, 2022. [Courtesy, William Ruto]

Former Nairobi Governor Mike Sonko has joined Deputy President William Ruto's Kenya Kwanza Alliance.

This comes after his bid to become the next Mombasa governor on Wiper Party ticket failed upon the upholding of his impeachment by Kenya's highest court, the Supreme Court.

Deputy President William Ruto on Saturday, July 30 took to Twitter to announce that Sonko had joined Kenya Kwanza.

"We welcome @MikeSonko to Kenya Kwanza, the winning team," Ruto said on the social media platform, attaching pictures of him and the former Nairobi County chief.

After the High Court in Mombasa ruled this week that IEBC's revocation of Sonko's clearance certificate was valid, Sonko threatened to support Hassan Omar, who is running for Mombasa governorship on the United Democratic Alliance (UDA) ticket.

Sonko is regarded as a crowds-mobiliser, who has a strong appeal to low-income earners in the society.

His addition to Kenya Kwanza, could pose a threat to ODM's Abdullswamad Sheriff Nassir, who is seeking to succeed outgoing Mombasa governor Ali Hassan Joho.

A May 2022 TIFA opinion poll placed Nassir's support base in Mombasa at 40 per cent, followed by Sonko at 28 per cent.

In Mombasa, there is a significant population of residents who come from rural Kenya, and had aligned themselves towards Sonko.