WASHINGTON (AP) — The Federal Reserve is set to cut its benchmark interest rate Wednesday for a third time this year to help sustain the U.S. economic expansion in the face of widespread trade tensions and slower global growth.

But the Fed's policymakers will likely frustrate anyone who is hoping for a clear signal about what they may do next. The central bank may prefer instead to keep its options open, economists say.

Analysts have forecast that the Fed will reduce the short-term rate it controls — which influences a broad range of consumer and business loans — by one-quarter percentage point year to a range of 1.5% to 1.75%. A third cut would nearly reverse the four rate hikes that the Fed made last year in response to a strengthening economy.

That was before rising global risks led the Fed to change course and begin easing credit. Lower rates are intended to encourage more borrowing and spending.

Chairman Jerome Powell has said that the central bank's rate reductions are intended as a kind of insurance against threats to the economy, notably from President Donald Trump's trade war with China and weaker growth in Europe and Asia. Powell has pointed to similar rate cuts in 1995 and 1998 as precedents; in both cases, the Fed cut rates three times.

The key issue at this week's meeting is whether the Fed has taken out enough insurance. Powell and most other Fed officials credit their rate cuts with lowering mortgage rates, boosting home sales and generally keeping the economy on track.

The Fed will also consider the consequences of a decline in expectations for inflation. Lower inflation expectations can be self-fulfilling. That represents a problem for the Fed because its preferred inflation gauge has been stuck below its 2% target for most of the past seven years.

In the meantime, Trump, via Twitter, has renewed his attacks on the Fed for not lowering its benchmark rate closer to zero. Trump has contrasted the Fed's actions unfavorably with central banks in Europe and Japan, which have slashed their rates into negative territory.

Though Trump has suggested that this puts the United States at a competitive disadvantage, most economists regard negative interest rates as a sign of weakness.

Some international tensions have eased since the Fed's last meeting in mid-September, which might suggest that further rate cuts are less necessary. The U.S. and China reached a temporary trade truce earlier this month and are working on a preliminary agreement that could be signed by Trump and President Xi Jinping in November.

It's not clear, though, how meaningful any such agreement might be, and Trump hasn't dropped his threat to impose new tariffs on Chinese goods on Dec. 15.

Another source of international tension has been Brexit, which has also eased. The European Union agreed Tuesday to delay the deadline for Britain's exit from the trade bloc to Jan. 31 from Oct. 31. That postpones what could have been a disruptive exit, right after the Fed meeting concluded, that would likely have damaged the U.K. and European economies.

The U.S. economy is still growing, and hiring remains steady, though there have been signs of a slowdown in recent data.

Americans cut back on spending at retailers and restaurants last month, a worrisome sign because consumer spending is the leading source of economic growth. Still, consumer confidence remains high, and shoppers could easily rebound in the coming months.

And businesses have reduced their spending on industrial machinery and other equipment, mostly because the U.S.-China trade war has made them reluctant to commit to big purchases. The tit-for-tat tariffs between the U.S. and China, the world's two largest economies, have also reduced U.S. exports.

Earlier Wednesday, the government will issue its first estimate of how the economy fared in the July-September quarter, and most economists have forecast that it will be relatively weak. The Atlanta Federal Reserve Bank projects that the economy expanded at just a 1.7% annual rate in the July-September quarter, which would be the second-slowest quarterly growth in nearly four years.

The job market remains sturdy, with the unemployment rate at just 3.5%, the lowest in 50 years. Steady hiring and decent wage increases should help underpin consumer spending in the coming months, keeping the economy expanding. That could keep the Fed on the sidelines in future meetings.

The housing market has also improved, after slumping in 2018, thanks in part to the Fed's rate cuts. Mortgage rates have fallen more than a full percentage point from a year ago, on average, for a 30-year fixed rate loan.

That's helped boost sales of existing homes while sales of new homes have soared. Auto purchases, another interest rate-sensitive industry, have also picked up.