Government spokesman Retired Colonel Cyrus Oguna on Thursday explained the legality of the Mau evictions.
Speaking to members of the press, he said that the areas that people were being asked to move away from were gazetted areas.
He contended that the people living in the forested areas were doing so illegally and had no justification.
"It is legal in the sense that if you are sitting on a place illegally then you have got no justification to be there. These are all gazetted forested areas and they have to be protected, " the Government Spokesman said.
Oguna's strong words come amid opposition from a section of Rift Valley leaders who contend that the government's eviction plan is unconstitutional.
In a strongly-worded statement on Thursday, Nandi Senator Samson Cherargei said that leaders opposed to the evictions would not relent on their opposition.
Environment Cabinet Secretary Keriako Tobiko said that ridding Mau of human habitation was all about environmental preservation.
Politicians against the controversial eviction have framed the Mau debate in humanitarian terms.
There were indications that the order to move from the forest was being heeded to as sections of the media shared videos of people moving out of the zone.