President Uhuru Kenyatta is expected to address at least 20,000 delegates from western Kenya at the Approved School in Kakamega.
The delegates are drawn from Vihiga, Kakamega, Busia and Bungoma counties.
The President is on a visit to western, a region considered to be opposition stronghold.
The meeting comes after President Kenyatta and his Deputy William Ruto campaigned in Busia and Bungoma counties on Friday.
He defended the amendments to the election laws saying they will seal loopholes that led to the nullifying of the presidential election held on August 8.
The President is expected to attend the homecoming party of Mumias East MP Benjamin Washiali at Malala.