CHICAGO (AP) – Illinois Congressman Adam Kinzinger says he cannot support Republican presidential candidate Donald Trump.

During an appearance Wednesday on CNN, Kinzinger said he is unlikely to vote for Trump because the nominee was “beginning to cross a lot of red lines of the unforgivable in politics.” CBS-Chicago reports that in an email, Kinzinger’s spokeswoman Maura Gillespie wrote the 16th District congressman has said he wants to support Trump. However, Kinzinger “doesn’t see a path to get there at this time.”

In the statement, Gillespie said Kinzinger will support his colleagues in Illinois and the Congress, and “continue to put the good of the country above partisan politics.”

Republican frustrations with Trump grew Wednesday as party leaders scrambled to persuade him to abandon divisive tactics that have triggered sinking poll numbers and low morale.