Kanu will keep an agreement it signed with the Jubilee government and is not willing to join another alliance ahead of the 2017 elections, according to chairman Gideon Moi.
Gideon said Kanu has an existing pact with Jubilee, which they signed after the 2013 General Election and they are not ready to break it to enter into another one.
"Kanu respects its obligations and until the expiry of the agreement, we are not in a hurry to get into another political agreement. As far as I am concerned, Kanu will honour the existing pact for now," he said.
Gideon, who spoke in Mombasa on Saturday during public hearings on the Local Content Bill, said his party is not part of any other coalition.
"We have not entered a new coalition," said Gideon who was accompanied by some members of the Senate Committee on Energy.
His announcement is a major setback for the much-touted National Super Alliance (Nasa) being spearheaded by Amani National Congress leader Musalia Mudavadi.
Those behind Nasa are hoping to bring all opposition parties into a major alliance as they fight to supplant the Jubilee administration in next year's elections where President Uhuru Kenyatta will be seeking re-election.
Although Kanu leaders, among them West Pokot Senator John Lonyangapuo, have dismissed Nasa, Gideon was seen as supporting the idea when he attended Bomet Governor Isaac Ruto's homecoming party where formation of the new alliance dominated speeches.
Several Opposition leaders in attendance, including Mudavadi, Kalonzo Musyoka and Kakamega Governor Whycliffe Oparanya drummed up support for Nasa, saying it was the only way to kick out Jubilee, which they accused of corruption.
Gideon's presence at the function raised hopes of Nasa proponents that Kanu would join Opposition efforts ahead of elections.
But in Bomet, Gideon was cautious, only saying he would talk to leaders of other political parties and coalitions at a later date.
Gideon has been popularising Kanu. He has concentrated his efforts in the Rift Valley in what pundits have termed a plot to eat away Deputy President William Ruto's support in the region.
Prof Lonyangapuo, who was recently installed as a Pokot spokesperson, has also been traversing pastoralist regions drumming up support for Kanu. "Kanu is a force in the Rift Valley and the reason we are seeing the DP and his lieutenants running around abusing us," he said.