Sinn Fein's push for an Irish Language Act is "yet another Trojan horse to be used in a campaign against unionism", the UUP leader has said.
One of the key stumbling blocks in the talks to restore Stormont has been Sinn Fein's insistence on a standalone Irish Language Act - which unionists will not agree to.
Ulster Unionist leader Robin Swann said Sinn Fein's "real reason" for wanting the Act is "to make Northern Ireland unrecognisable and turn it into a bilingual state".
"It's just another Trojan horse for Gerry Adams to use in his campaign against unionism," he said.
"Sinn Fein's push for an Irish Language Act is an attempt to balkanise Northern Ireland.
"They want the creation of a two-tier Civil Service, with a recruitment quota of 10%, and to give an Irish language commissioner the powers of a High Court judge to go after English speakers."