WASHINGTON – The Federal Reserve went further than ever Wednesday to assure consumers and businesses that they’ll be able to borrow cheaply well into the future.

The Fed pushed back the date for any likely increase in its benchmark interest rate by at least a year and a half, until late 2014 at the earliest.

Its new timetable showed the Fed is concerned that the economy’s recovery remains stubbornly slow.

But it also thinks inflation will stay tame enough for rates to remain at record lows without igniting price increases.

Chairman Ben Bernanke cautioned that its late-2014 horizon for any rate increase is merely the Fed’s “best guess.” It has the flexibility to change its mind if the economic picture changes.

But speaking at a news conference later Wednesday, Bernanke said:

“Unless there is a substantial strengthening of the economy in the near term, it’s a pretty good guess we will be keeping rates low for some time.”

The Fed reduced its outlook for growth this year but is slightly more optimistic about the unemployment rate.

It expects the economy to grow between 2.2 percent and 2.7 percent this year.

That’s down from its November’s forecast of between 2.5 percent and 2.9 percent.

But it sees unemployment falling as low as 8.2 percent this year, better than its earlier forecast of 8.5 percent. December’s rate was 8.5 percent.

The quarterly updated forecast also shows some Fed members wanted to extend the period of record-low interest rates beyond late 2014.

The Fed also offered a firmer target for inflation – 2 percent – in a statement of its long-term policy goals.

Treasury yields fell on the news that the Fed plans no rate increase until late 2014 at the earliest.

Lower yields could help further reduce mortgage rates and possibly boost stock prices as investors shift out of lower-yielding Treasurys.

The central bank said in a statement after a two-day policy meeting that the economy is growing moderately, despite some slowing in global growth.

It held off on any further bond-buying programs to try to increase growth.

The Fed held out the possibility of buying bonds later. It said it was prepared to adjust its “holdings as appropriate to promote a stronger economic recovery in the context of price stability.”

Some economists say that means the Fed will take further action soon.

Julie Coronado, an economist at BNP Paribas, said the Fed is signaling it will boost its purchases of bonds and other assets if growth fails to accelerate, even if the economy doesn’t slow.

That is a “very low bar indeed,” she wrote in a note to clients.

The Fed described inflation as “subdued.”

That was a more encouraging description than it offered last month. A more positive outlook on prices gives the Fed more room to keep rates low.

“This is a fairly clear-cut signal that inflation is not on their radar at this point,” Tom Porcelli, an economist at RBC Capital Markets, wrote in a research note.