Former Garsen MP Danson Mungatana has told ODM party leader Raila Odinga to stop forcing Coast politicians to remain in Cord.
Mungatana said every Kenyan has the right to make political choices without influence.
He said politicians who have ditched the opposition coalition were tired of associating with a political outfit that loses in every election.
"Raila cannot force people to remain in the opposition, years have passed and people must accept change," he was quoted by the Star as saying on Sunday.
"If Coast people loved him all those years, the love has now faded."
Raila on Friday concluded a five-day tour of the Coast after visiting the counties of Mombasa, Tana River, Kilifi and Kwale.
The opposition chief is seeking to marshal support for the ODM party and Cord as the country moves close to the 2017 elections.
There has been growing opposition from the region that overwhelmingly voted for him in 2013 with notable politicians decamping to the newly launched Jubilee Party led by President Uhuru Kenyatta.
Kwale Governor Salim Mvurya recently defected to the Jubilee Party, joining MPs Gideon Mung’aro (Kilifi North), Mustafa Idd (Kilifi South), Khatib Mwashetani (Lunga Lunga) and Kwale woman representative Zainab Chidzuga.
They claimed ODM lacks internal democracy and that dissenting voices within the party are fought against.
Mungatana was speaking in Bondeni, Galole constituency in Tana River County.
He told residents of the county to vote for President Uhuru Kenyatta in 2017.