Armed police officers have set up checkpoints on roads leading to State House in Nairobi, the capital, amid fears of planned opposition protests.
Drivers are being stopped and searched at various points along the highway.
It comes after the opposition issued a 14-day ultimatum to the government to address concerns about the high cost of living.
Raila Odinga, the opposition leader, has been leading a series of anti-government rallies across the country.
