WASHINGTON (MarketWatch) — Leading supporters of the Federal Reserve’s bond-buying program are not rushing to scale back the pace of purchases as the job market improves.

In an interview with reporters, Charles Evans, the president of the Chicago Federal Reserve Bank, and a leading architect of the Fed’s ultra-loose policy, counseled a go-slow approach to making any changes to the $85-billion-a-month per month purchases of Treasurys and mortgage-backed securities.

“I think this is the point where we have to be patient and let our policies work,” Evans told reporters over breakfast.

“I prefer and think it is best that we continue to provide strong confidence that we are going to be doing appropriate accommodative policies to get the economy going again,” he said.

Other leading doves on the central bank, Eric Rosengren of the Boston Fed and Narayana Kocherlakota of the Minneapolis Fed Bank, also gave speeches that showed no rush to taper the program.

Rosengren and Evans both said they expected the asset purchases to last through 2013.

Evans said the Fed will have to have confidence that the economy was on solid footing in the second half of the year before changing policy.

“That could easily mean that we need to work our way through the second half before we have enough confidence that growth is strong enough,” Evans said.

Some other Fed officials are eager for the Fed to scale-back the asset purchases. A few believe the Fed should start tapering as soon as possible.

Dennis Lockhart, President, Federal Reserve Bank of Atlanta, and Charles Evans (left), President and CEO, Federal Reserve Bank of Chicago, take part in a panel discussion titled "Twist and Shout: The Limits of U.S. Monetary Policy" at the Milken Institute Global Conference in Beverly Hills, California May 1, 2012. Reuters

Sandra Pianalto, the president of the Cleveland Fed Bank, is more moderate. In a speech to an accounting group, Pianalto said the asset purchases could be scaled back if the economy continues gather momentum.

“That outcome could emerge before long, but it still remains to be seen,” Pianalto said.

The Fed is currently buying $45 billion in long-term Treasurys and $40 billion of mortgage-backed securities each month. After a two-day meeting last week, Fed Chairman Ben Bernanke said the Fed wanted to be convinced that recent improvement in the labor market was sustainable before curbing the purchases. Read ‘Fed still unconvinced of job-market healing’

William Dudley, the president of the New York Fed, said in a speech Monday that he expected the fed would eventually scale back the pace of the purchases.

But Evans argued that the asset purchases were helping the economy.

“I can’t see that those are the parameters for doing less,” Evans said.

“I want to be really careful” about the signal that reducing bond-buying would be, he said.

Evans said he was open-minded and a couple of months of job growth over 300,000 would get his attention. In February, 236,000 jobs were created.

Evans and Rosengren downplayed potential costs of the program.

Evans said the benefits of the purchases dwarf the potential costs. “At the moment, it is not even a close call,” he said.

Critics of asset purchases view them as inflationary. But Rosengren said that these criticism “has become more muted” with the purchases going on for five years of stable inflation.