Health workers countrywide went on strike on Monday after talks with the ministry collapsed the previous evening, warning that it will be the longest in history.
The medics failed to show up for a meeting with Health Cabinet Secretary Cleopa Mailu on Sunday.
They downed their tools saying they want the 2013 central bargaining agreement implemented.
Samuel Oroko, national chairman of the Kenya Medical Practitioners Pharmacists and Dentist Union (KMPDU), said the government had not fulfilled its promises.
"It is time that the government listened to us. We have tried all avenues but it is not working. We will make them listen to us," he said.
"We only have two main issues - poor pay and deployment of our members. They must be addressed before we resume work. Nothing will stop us."
Oroko said the health workers will only resume duty after the full implementation of the CBA.
Comprising about 5,000 members, the union says the bargaining agreement was to give them a 300 per cent pay rise, review of their working conditions and job structures and criteria for promotions, and address under-staffing of medical professionals in state hospitals.
"We must be listened to... We have had lots and lots of diplomacy, and lots and lots of dialogue. Dialogue has to come to an end," the chairman said to cheers of doctors at a news conference before the march.
"We are sorry for Kenyans who end up suffering but this will not be resolved in any other way."
Nairobi health workers during a meeting at Public Service Club, before their march in a demonstration over the government's failure to implement the 2013 central bargaining agreement, December 5, 2016. /MONICAH MWANGI
The health workers asked the public to prepare for the longest strike ever; they said they will not report to work and that if they do, no patients will be admitted.
Police fired tear gas to disperse hundreds of them who marched to the Health ministry headquarters and then to the Finance ministry's.
Mailu earlier said the strike was premature as the 90 days a court gave for negotiations had not lapsed.
Noting the ministry was still open to talks, he urged the medics to report to work and prevent a health crisis that may lead to the loss of lives.
" This strike notice is premature. On October 6, Justice Monicah Mbaru directed the Salaries and Remuneration Commission to reconvene and solve contentious issues including salaries in 45 days," he said.
"The judge also directed the ministry to submit the pact in court for registration within 90 days after it was finalised."
He added that the 21-day day strike notice issued by the medics was in bad faith.
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