Azimio leader Raila Odinga on Tuesday met with the Bunge la Mwananchi members.
Raila's meeting with the group was occasioned by their invitation.
The opposition chief used the meeting to ask the group to vigilant and defend the democratic gains the country has trained.
"I listened and encouraged them to remain vigilant of our hard-won constitutional rights. Freedom of association and speech is a key pillar of our democracy," Raila said.
Earlier, Raila faulted the current regime of President William Ruto for lifting subsidies.
He said the price of fuel will this week hit a record high again.
Raila defended former President Uhuru Kenyatta saying he knew how to protect Kenyans adding that Ruto has failed to do so for the few days he has been in office.
"Every time they were blaming Uhuru but he was doing what other heads of state were doing worldwide. Uhuru protected Kenyans from the effects of the Russia and Ukraine wars. But now they have said that it is unsustainable, this week the price of fuel will go up again," Raila said.
Raila said that President William Ruto had promised to lower the cost of fuel but it has instead gone up.
He was accompanied by Embakasi MP Babu Owino and Lang'ata MP Felix Odiwour among other leaders.