Speaking on Tuesday during an interview on KTN, Odinga downplayed the move saying it did not reduce his votes in the Meru region and acknowledged that he had received a message from Munya prior to his departure.
"I had received a message from him telling me he was under a lot of pressure. He had no other choice.
"I understand and I have excused him," stated Odinga.
He expressed confidence in getting votes in Meru despite the setback, saying he still got votes when Munya was in Jubilee.
"My support in Meru is still intact. I got a lot of votes when he (Munya) was in Jubilee. He has been campaigning for me until yesterday," he added.
The former Meru governor ditched the opposition coalition yesterday, just a week after joining the Odinga-led NASA team. Munya led a delegation of PNU Party officials to State House where they reached an agreement to rally behind President Uhuru Kenyatta ahead of the October 17 elections.
Tweeting on his official account, President Kenyatta said Munya and other PNU party officials pledged to support his re-election bid following consultations at State House, Nairobi.
In a statement to newsrooms, the Party of National Unity (PNU) said that following consultations, the decision to support President Kenyatta is in the best interest of the country.