More mixed signals Tuesday on the state of the economy from Federal Reserve board members.

The conflicting messages from Minnesota Fed President Narayana Kocherlakota, an inflation dove, and Richmond Fed President Jeffrey Lacker, an inflation hawk, highlight the growing debate at the central bank over the timing and trajectory for raising interest rates.

In separate speeches, the two influential Fed members presented arguments for maintaining accommodative monetary policy, ie., keeping interest rates at their historic lows, and inversely for lowering them sooner than anticipated.

Kocherlakota said in prepared remarks that it might be another five years before inflation stabilizes at the Fed’s target rate of 2%. Annual price growth is far more likely to remain below 2% over the next half decade than above it, Kocherlakota said.

"We need to do better," the central banker said, of the Fed's fight to heat up economic growth and inflation.

Kocherlakota is firmly in the camp of Fed chair Janet Yellen, who has strongly advocated maintaining economic stimulus for as long as needed to ensure the economy can hold its own before completely phasing out the easy-money policies.

Kocherlakota did not offer a forecast in his prepared remarks as to when he believes interest rates should be raised from their current near-zero level.

Lacker, a long-time vocal inflation hawk, cautioned in a speech that the Fed needs to be vigilant toward inflation.

“Inflation, meanwhile, remains well-behaved, but maintaining that good performance will require withdrawing monetary stimulus at an appropriate time to prevent the emergence of inflationary pressures,” Lacker said.

While raising the notion of higher rates, Lacker also gave no timetable for when rates might move higher.

Kocherlakota and Lacker also offered differing views on U.S. labor markets. The U.S. added 288,000 jobs in June and the unemployment rate now stands at 6.1%, a six-year low.

Yet Kocherlakota reiterated the doves’ position that labor markets aren’t as strong as the monthly numbers suggest: “The good news is that the labor market has improved since the end of the Great Recession. The bad news is that the rate of improvement over the past four-plus years has been painfully slow,” he said.

Lacker said there’s less “slack” in labor markets than has been suggested by doves.

Inflation doves have advocated keeping interest rates low for the foreseeable future to stimulate the economy because “slack” in labor markets has prevented millions of Americans from finding well-paying, full-time jobs.

Hawks believe keeping rates too low for too long will push prices higher and lead to runaway inflation.

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