March 5 (Reuters) - The recent run-up in yields on longer-dated U.S. Treasury securities reflects improving expectations for the economy, St. Louis Federal Reserve President James Bullard said on Friday, adding that he is not eyeing a specific level of yields that might concern him.

The 10-year U.S. Treasury note yield - which rose above 1.62% on Friday before falling back to about 1.55% - is just returning to the level consistent with the six months before the coronavirus pandemic, Bullard said in an interview on SiriusXM Radio, characterizing it as "still quite a low level of yields."

Echoing Fed Chair Jerome Powell's comments from a day earlier, Bullard said he would be concerned by disorderly behavior in the Treasury market. "Something panicky would catch my attention, but we're not at that point."

Bullard also dismissed the need for the U.S. central bank to take specific action any time soon to cap the rise in yields through an "Operation Twist" - or a shift in the Fed's $80 billion a month in Treasury purchases toward longer maturities that would put downward pressure on their yields. The Fed executed such a move about a decade ago as the economy was recovering from the 2008 financial crisis.

"It's not matching up right now that we need to be more dovish than we already are," Bullard said.

Asked about the prospect for additional fiscal stimulus beyond the Biden administration's proposed $1.9 trillion relief bill now before Congress, Bullard said he was "skeptical" about such a package getting enacted, adding he sees it as only a 50% probability.

Bullard reiterated his own recent forecast for the U.S. jobless rate to end the year at around 4.5% and that gross domestic product growth could be around 6.5% as the rollout of COVID-19 vaccines and diminishing infection rates allow for a broader resumption of economic activity. The Labor Department reported earlier on Friday that the nation's unemployment rate dipped 0.1 percentage point to 6.2% last month.

Nonetheless, he said, we "still need a lot of repair" in the labor market. (Reporting by Dan Burns Editing by Chizu Nomiyama and Paul Simao)