WASHINGTON (Reuters) - A drop in the consumer outlook for inflation and intensifying trade tensions drew caution from Federal Reserve officials on Monday as policymakers faced fresh market volatility and a renewed set of risks.

FILE PHOTO - Shoppers ride escalators at the Beverly Center mall in Los Angeles, California November 8, 2013. REUTERS/David McNew/File Photo

While Fed officials have largely discounted the trade war so far as unlikely to derail the U.S. economic expansion, officials emphasized Monday that a protracted tit-for-tat battle between the United States and China was a different matter that might require a Fed response.

“If the impact of the tariffs - and whatever financial market reaction to those tariffs is - causes more of a slowdown, then we do have the tools available to us, including lower interest rates,” Boston Fed President Eric Rosengren, a voter this year on Fed rate policy, said in an interview with Reuters.

While Rosengren said he was “not necessarily” expecting a rate cut to be necessary, the market sell-off Monday was deep and potentially disruptive to the Fed’s core expectation that interest rates will remain on hold for some time to come.

Major U.S. equity markets were down between 2% and 3.5% on Monday, while bond investors sharply increased their bets that the Fed would be forced to cut rates this year. A closely watched spread between long- and short-term bonds turned negative, seen by some officials as a sign of weakened market confidence in the economic outlook.

After the collapse of U.S.-China talks last week and the threat of tariffs ratcheting ever higher, there was more reason to believe the tensions will last a while.

“If it’s the worst-case scenario and it’s ever-increasing tariffs for an extended period of time, that could change things, that could have a real effect on U.S. GDP growth,” Minneapolis Fed President Neel Kashkari said on CNBC.

Traders and analysts on Monday said the volatility is likely to continue.

“You cannot game what two leaders...are going to do from day to day,” said Anthony Saglimbene, global market strategist with Ameriprise Financial Services in Troy, Michigan, of the high-stakes standoff between Trump and Chinese President Xi Jinping.

RATE CUTS BACK ON RADAR

Fed officials have been careful to say that nothing yet has changed their core outlook, which envisions rates to be held in their current range of between 2.25% and 2.5% until either growth demonstrably weakens and inflation falls further, justifying a rate cut, or faster inflation makes higher rates warranted.

As the trade war intensified over the last few days, however, traders in the federal funds futures market have moved decisively in favor of expecting a Fed rate cut in coming months. Data from the CME Group now sees the Fed cutting rates in October, with a near 10 percentage point shift since Friday in the probability of a rate reduction at that Fed meeting.

The pressure on the Fed could come from several directions. Economic growth overall could slow if the tariff wars continue and global trade declines; “wealth effects” could directly impact business and household confidence and spending if the stock declines continue; higher costs could hit company profits, and discourage hiring.

A further complication for the Fed: The inflation outlook among U.S. consumers dipped sharply in April, countering Fed policymaker hopes that inflation dynamics will improve and the pace of price increases soon rise toward their target level.

Survey data released by the New York Federal Reserve on Monday showed consumer expectations of the inflation rate over the next year fell to 2.6% from 2.82% in the March survey. The nearly quarter point drop was the third-largest since the survey was launched in mid-2013. The outlook for inflation over the next three years also fell, to 2.69% from 2.86%, evidence that medium-term expectations have also weakened in recent weeks.

Following the Fed’s most recent meeting, Chairman Jerome Powell and others said they felt recent weak inflation readings were driven by “transitory” factors that would disappear over time and allow overall inflation to rise.

But a drop in inflation expectations is another matter, and could be evidence that households and businesses are losing faith in the Fed’s ability to deliver on its inflation goal - a worrying development for central bankers who feel their ability to keep expectations set around their inflation target is critical to meeting the goal.

As of the Fed’s last policy statement on May 1, officials said they felt expectations remained stable.

While consumer surveys are discounted by some officials as overly influenced by things like changes in gasoline prices and other costs that consumers closely monitor, some broader market expectation measures have also shifted. Since late April, for example, a St. Louis Federal Reserve measure of the inflation rate expected five years from now, based on trading in different types of bonds, dipped to 1.9% from 2.1%, a sign traders also see weaker inflation ahead.