New Delhi, Aug. 20 -- US Treasury Secretary Scott Bessent said increased buybacks of Treasury securities announced this week could be more than $4 billion per issue.

"We have a big toolkit, so we'll see," Bessent said Thursday on CNBC. "And part of it is signaling here, and to show that we believe that the yields don't reflect the underlying fundamentals."

Bessent spoke after the Treasury Department said Wednesday that it would increase "by at least double" the size of buybacks for longer-dated securities. The impact in the market was short-lived, with US 30-year bonds erasing gains from the surprise announcement by Thursday. Yields on 10-year and 30-year securities remained higher following his comments.

"All we're trying to do is get...