ODM party leader Raila Odinga has asked opposition supporters to steer the voter registration process.
Raila said unless Cord/ NASA supporters register as voters, Jubilee will retain power in August.
He spoke as he met other opposition leaders at the Bomas of Kenya to finalise talks on the formation of the National Super Alliance.
"To our supporters, we will deal with election Laws," he said in reference to the recent proposed Election Laws which, President Uhuru Kenyatta signed into law.
"We promise you that, but you must all go out, in every town, village, home, church, school, bus stop every single day and not rest until everybody you meet is a registered voter to send a mass message to Jubilee that they must go home! It has to be done."
Raila at the Bomas of Kenya met Wiper's Kalonzo Musyoka, ANC's Musalia Mudavadi and Ford Kenya's Moses Wetangula in what was described a meeting that signals NASA's formation is in the offing.
The alliance is expected to field a presidential candidate who will take on President Uhuru Kenyatta during the August general elections.
"It has been done elsewhere. It will be done here with your help and the backing of a united opposition."