Workers Sunday morning gathered at Uhuru Park in Nairobi to celebrate the 2016 Labour Day, amid a chilly weather.
During the celebrations, Central Organisation of Trade Unions (Cotu) Secretary-General Francis Atwoli lambasted employers for "misadvising" the government on how much employees should be paid.
Mr Atwoli said employers were insisting on paying workers based on productivity when there was no formula in place to gauge it.
It was a direct jab at the Federation of Kenya Employers (FKE) and Kenya Private Sector Alliance (Kepsa), who say the economy was doing badly despite annual minimum wage increments.
He spoke shortly after FKE CEO Jacqueline Mugo told a gathering attending Labour Day celebrations that Kenya needs to peg pay rise on each worker's deliverables.
The comment seemed to have irked Mr Atwoli who took his time to respond.
"Who is misadvising the government on productivity? I have heard you talking about productivity. The government has no way of measuring productivity and so FKE cannot pretend to know how to.
In a speech that lasted 50 minutes, Atwoli dwelt on the issue, asking Ms Mugo to document her own productivity at the employers' organisation.
"This language of productivity in Kenya cannot work. In Africa, it is only in South Africa where they have some semblance of productivity.
"If we abandon the guidelines of the government and go the way of this mama, this country will be in industrial chaos.
"If we are to be measured on productivity, what we are doing to our own families? Me and her, we have a shortfall. Her family will expel her and my two wives will chase me away.
"Tell the president that FKE and Kepsa are misadvising the government on the so-called productivity,” Mr Atwoli insisted.
The celebrations were attended by senior government officials and labour unions officials led by Cotu Secretary-General Francis Atwoli.
Cabinet Secretaries Adan Mohamed (Industrialisation), Dan Kazungu (Mining), Phyllis Kandie (Labour), Raychelle Omamo (Defence), Jacob Kaimenyi (Land and Housing), James Macharia (Roads) and Willy Bett (Agriculture) were among those present.
Others were CSs Mwangi Kiunjuri, Eugene Wamalwa, Fred Matiang’i and Sicily Kariuki.
Also present were the Ethiopian ambassador to Kenya Dina Mufti and Beyene Russom of Eritrea.
Speaking during the celebrations, Mr Atwoli thanked President Uhuru Kenyatta for spearheading the revival of Pan Paper Mills.
He called on the government to improve terms for those working in the countries security agencies.
He also called Cabinet secretaries to respect boards that run State parastatals.