The government has declared NASA's National Resistance Movement as an organised criminal group.
The NRM was formed on October 25, 2017, a day before the repeat polls were held.
"In the exercise on the powers conferred by section 22 of the Prevention Organised Crimes Act, 2010, Ministry of Interior and Co-ordination of National Government declares the National Resistance Movement to be an organised criminal group for the purposes of the Act," Interior CS Fred Matiang'i said in a statement on Tuesday.
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The opposition formed the movement to lead its supporters in civil disobedience to pile pressure on President Uhuru Kenyatta's government to step aside.
On November 3, the NRM asked supporters to boycott products and services by Safaricom, Brookside and Bidco as part of the resistance movement.
The leaders noted the boycott was part of the economic liberation scheme supported by the People's Assembly.
At a press conference on October 25, Raila said he will work with the people to protect the constitution.
He reiterated the boycott threat, saying there are many ways to kill a cat, and said the people should take instructions to boycott newspapers, TV stations, products and services in their bid for change in Kenya.