The government is yet to release the Sh2.5 billion which DP William Ruto promised maize farmers last week.
The amount is part of the Sh5 billion which the NCPB has owed farmers since December last year, for the more than 3.8 million bags they delivered.
The Deputy President had said the cash would be given to the board but farmers have expressed disappointment due to lack of it.
Moiben MP Sila Tiren faulted the government for lying to farmers over the release of the money.
“As I said last week, the money will not be released because the government is now used to lying to farmers," he told farmers at the NCPB depot in Eldoret on Saturday.
The MP regretted that the government has been contradicting itself by promising payment while asking farmers to sign forms indicating they will be paid in the next financial year.
Farmers have threatened to resume protests at the depots of the National Cereals and Produce Board in the region.
“We are being fooled. We will have to paralyse NCPB operations if the money is not released," Kipkorir Menjo, who is Director of the Kenya Farmers Association, said.
The farmers have also blamed the government for allowing maize imports that have caused price drops.
Traders and some farmers bought the maize for Sh1,800 per bag in Uganda and sold much of it to the NCPB for Sh3,200 per bag.
More than 300 lorries, some suspected to have imported maize, are still lining up to deliver maize at depots in the North Rift, which have been closed for lack of space.
Information from the NCPB shows it bought 3.8 million bags, half of it said to have been from Uganda.
Harsame Kello, the secretary in charge of crops at the Ministry of Agriculture Harsame Kello, said some farmers supplied maize in excess of what they can produce on their farms.
"It’s clear they brought imported maize to the NCPB," he said.
A farmer from Moiben has been identified as the biggest importer - she has 60 acres of land and can only produce a maximum of 2,400 bags but she gave the board 9,000.
“We have more than three million bags of maize from Uganda, which has a surplus of more than seven million bags of maize this year,” East African Grain Council member James Olwechi said
Speaking in Uasin Gishu a week ago, Ruto complained that brokers were frustrating farmers by importing too much maize.
The cheap imports have pushed the price of maize in the region down to Sh2,000 per bag.
Meanwhile, farmers in the Rift Valley have signed an agreement on new conditions set by the government before the release of their payment.
The new rules prohibit them from demanding payment for deliveries for three months.
They will also be vetted on their farms before being allowed to move their maize to the depots.
"The aim is to weed out brokers who have been disguising themselves as farmers and ensure we deal with only genuine ones," Kello said.