Opposition party ODM has refuted claims that Nasa has settled on Wiper leader Kalonzo Musyoka as its flag bearer.
National Super Alliance leaders did not name a presidential candidate after signing an agreement on Wednesday.
Their deal outlined seven key pillars on they will anchor their campaign to remove President Uhuru Kenyatta from power..
Moments after, a statement purporting that Kalonzo would be the coalition's flag bearer was widely shared on social media.
ODM communications director Philip Etale accused Jubilee of spreading the lies.
"Jubilee, you will forever be desperate. Even your desperation will not make Jesus notice you when he comes back," Etale said on Twitter.
"Even a silly dog in the village will know the document Jubilee is spreading around is as fake as their ideas," he added.