Treasury Secretary Janet Yellen warned that the department will probably exhaust its ability to avoid breaching the federal debt limit sometime in October, sending a message to congressional leaders as she prepares to step up talks with lawmakers on boosting or suspending the ceiling.

"Based on our best and most recent information, the most likely outcome is that cash and extraordinary measures will be exhausted during the month of October," Yellen said in a letter to Congress Wednesday. "We will continue to update Congress as more information becomes available."

Senate Majority Leader Charles Schumer and House Speaker Nancy Pelosi said separately Wednesday that there were multiple options to resolve the debt-limit question, without specifying them.