Republican Sen. Pat Toomey said Thursday it's "unbelievable" that interest rates remain so low and it's time to end the Federal Reserve's "subjective" moving of the goal post.

"The Fed no longer has credibility, and you can see that. The divergence between the futures markets and the Fed's own projections about what they're going to do about interest rates—this is a huge problem," he told CNBC's "Squawk Box."