Mr Atwoli made the remarks on Saturday while in Lamu where he said DP Ruto is wasting his time campaigning for the presidency.
Mr Duale has warned the trade unionist to tread carefully, warning his utterances are divisive and can cause tribal clashes.
A section of MPs led by National Assembly Majority Leader Aden Duale have criticised trade unionist Francis Atwoli's over his utterances that Deputy President (DP) William Ruto will not be in the ballot in the 2022 presidential elections.
The secretary-general of the Central Organisation of Trade Unions made the remarks on Saturday while in Lamu where he claimed Mr Ruto is wasting his time campaigning for the presidency.
Speaking on Sunday at an event in Ng’ombeni in Matuga Constituency, Mr Duale warned the trade unionist to tread carefully, saying his utterances are divisive.
“He should tell us what he meant by the utterances that the DP will not be in the ballot. As leaders from various backgrounds in the country, we must be careful on what we say because our utterances can cause division and tribal clashes in the country and our agenda is to unite all Kenyans," said Mr Duale.
Mr Duale also dismissed claims of deep divisions in Jubilee Party.
"Don't listen to those going round telling lies about Jubilee, but instead ask me because I'm the official spokesperson of the party in the National Assembly and my position is enshrined in the Constitution," he said, adding that those very few who are making noise are hired people.
Mr Duale said he will not allow “hired people” to speak for the party with intent to break it up.
The Garissa Town MP was accompanied by MP Kassim Tandaza (Matuga), Mr Khatib Mwashetani (Lunga Lunga), Mr Suleiman Dori (Msambweni), Mr Stanley Muthama ( Lamu West), Mr Omar Mwinyi ( Changamwe) and Tana River Woman Representative Rehema Hassan.
Other leaders who spoke at the event warned Mr Atwoli to tame his tongue and concentrate on the welfare of the workers and leave Mr Ruto alone.
Mr Muthama lashed out at Mr Atwoli, saying Lamu people would not welcome him “if he is coming to insult other leaders”.
“Atwoli spoke nonsense when he came to our county. Instead of speaking about what had taken him there, he went to insult people but we are telling him that we will not spare him. We will deal with him,” said Mr Muthama.
Mr Mwashetani accused Mr Atwoli of peddling lies against Mr Ruto over corruption.
“If you think someone is corrupt and you have evidence then take it to the Directorate of Criminal Investigations and Director of Public Prosecutions. If Atwoli is interested in politics, he should say so that we deal with him,” said Mr Mwashetani.