Bosire, who previously served as the Member of Parliament for Kitutu Masaba in Kisii County, announced his decision to leave the party in late February 2026.
He expressed his dissatisfaction with ODM’s current trajectory, highlighting internal conflicts and what he sees as a loss of focus.
His departure comes at a critical time for the party, which is already dealing with leadership uncertainty and realignments in the wake of the death of long-time leader Raila Odinga.
As the 2027 General Election approaches, various ODM leaders are reportedly strategizing to secure their positions of influence.
Despite having previously denied any intention to launch a new party, recent events seem to have influenced Bosire's choice. Insiders suggest he feels a new political platform is crucial for fostering alternative ideas and leadership styles.
Bosire will lead the newly formed United National Congress, which has appointed former Busia Woman Representative Florence Mutua among its officials.
The party’s founders have stated that their focus will be on promoting national unity, enacting governance reforms, and ensuring accountability in leadership.
There are also suggestions that the party may align with former Interior Cabinet Secretary Fred Matiang’i, who is perceived as a key figure in the Gusii region and is rumored to be eyeing a significant political role ahead of the 2027 elections.
Analysts view Bosire's departure as a potential blow to ODM, especially in Kisii and Nyamira, where the party traditionally enjoys strong support. Observers warn that more defections could follow if the party doesn’t address its internal issues.
Furthermore, ODM's cooperation with President William Ruto’s United Democratic Alliance has faced criticism from some supporters who feel this partnership has shifted the party away from its traditional stance as the opposition.
As UNC emerges, the political landscape is gradually changing, with new parties and alliances gearing up for the upcoming electoral cycle.
ODM leaders have yet to respond comprehensively to Bosire’s resignation, leaving questions about whether the new party will gain traction on a national level or remain focused on regional interests.