Opposition chief Raila Odinga will on Saturday be in Mombasa and is expected to make a major political announcement.
There is already panic within the ruling Jubilee coalition over whether the declaration will in any way negatively impact the coalition's deliberations during that day.
The Mombasa declaration will be made as Jubilee politicians will be launching the Jubilee Party which President Uhuru Kenyatta will ride on to defend his seat in 2017.
A statement released by ODM Deputy Party leader and Mombasa Governor Hassan Joho on Tuesday said the announcement will be made during celebrations to mark ten years of ODM's existance.
ODM senators, governors, MPs and women reps will be in attendance.
"The Change Movement is coming home to Mombasa," Joho's statement read in part.
"I officially announce that our great county will host ODM’s '10 at 10' celebration scheduled for this Saturday, September 10 – an extravaganza that will inspire the hearts and minds of the people of the republic."
"On that day, Kenyans will be reminded of the rich history of our party and will see for themselves the great vision we have for the next ten years."
It's still not known whether Mr Odinga will contest for the presidency in 2017 or he will endorse someone else to challenge Mr Kenyatta.
Cord co-principals Kalonzo Musyoka, Moses Wetangula and Amani National Congress leader Musalia Mudavadi have asked Mr Odinga to support their bid to become Kenya's fifth president.