The longer they wait, the more agitated U.S. Federal Reserve Board chairman Ben Bernanke becomes over the unwillingness of U.S. lawmakers to get serious about the country’s budget deficit.

Appearing before a congressional committee for the fifth time since January, Mr. Bernanke on Tuesday delivered his strongest warning yet about waiting to narrow the widest fiscal shortfall since the Great Depression.

On a day when surveys of purchasing managers from China to Europe to the United States flagged the possibility that surging commodity prices might soon feed into the costs of manufactured goods, the Fed chairman, while not ignoring inflation, was most concerned about the state of the U.S. government’s finances.

Mr. Bernanke said the deficit is the single biggest issue facing the economy, characterizing the near-record shortfall as a “near and present danger” that could trigger a financial crisis on the scale of the one that drove the global economy into recession in 2008.

After spending hundreds of billions to boost demand during the global recession, richer countries are struggling to shrink swollen deficits amid tepid economic growth and high unemployment rates. The European debt crisis shows investors will punish governments that fail to get their finances under control by driving up interest rates to punishing levels, and that is the fear in the United States.

“It’s really a very worrisome situation,” Mr. Bernanke said in testimony at the Senate banking committee on Tuesday.

Mr. Bernanke’s increasingly urgent appeals to the U.S. Congress on the deficit are significant because even after six years as the country’s top central banker, the Fed chief rarely seeks to influence political decisions.

Alan Greenspan, the previous Fed chairman, was famous for putting his name behind legislative initiatives he supported, such as George W. Bush’s tax cuts.

Mr. Bernanke, on the other hand, is so careful about entering the political fray that he has avoided uttering a strong opinion on the attempt by some Republican lawmakers to remove job creation from the Fed’s mandate.

“We are not seeking any change,” Mr. Bernanke said Tuesday when asked about the push to have the Fed focus only on inflation. “We will do whatever Congress tells us to do.”

But when it comes to the $1.6-trillion (U.S.) deficit, Mr. Bernanke is bolder at telling his congressional masters what he thinks.

For months, Mr. Bernanke has used appearances on Capitol Hill and elsewhere to bridge the gap between Republicans who would slash government spending immediately and Democrats who worry that an austerity program would kill the economic recovery.

The Fed chairman’s message is a mix of the two: Draw up a rigorous deficit-reduction program, but delay its implementation until the economy is comfortably on track.

This also is the approach advocated by neutral observers of the U.S. situation, such as the International Monetary Fund and President Barack Obama’s debt-and-deficit commission.

The idea is to keep the bond vigilantes at bay. If investors are reasonably confident that U.S. politicians are serious about the country’s fiscal problems, they will continue to lend the government money at reasonable rates.

But if investors lose faith, the cost of financing a public debt that is projected to climb to $17-trillion by 2020 will become more expensive, making the current fiscal challenge even harder.

The reason for urgency is that it is impossible to know when market sentiment will turn.

“If it became clear that these problems were not going to be adequately addressed because we were just in a perpetual gridlock, I think that would raise significant concerns that would bring these problems forward into the present,” Mr. Bernanke told senators.

It’s difficult to judge whether Mr. Bernanke’s entreaties are having any impact.

There are reports of lawmakers quietly trying to build a bipartisan consensus on a long-term budget strategy based on the report of Mr. Obama’s deficit commission, which proposed a combination of spending cuts and tax increases worth $4-trillion over 10 years.

Publicly, it’s another matter.

Democratic and Republican lawmakers have yet to agree to a budget for the current fiscal year, which began five months ago. The new Republican leaders of the House of Representatives are in a standoff with their Democratic counterparts in the Senate over making immediate budget reductions.

The House on Wednesday approved a stopgap budget bill designed to avert a government shutdown on Friday. The measure would extend spending authority for two weeks, while trimming $4-billion from the budget.

Senate Majority Leader Harry Reid said his chamber would pass the measure and forward it to Mr. Obama by the end of the week.

The compromise shows each party is keen to avert a government shutdown, which would mean unemployment cheques and social security payments would go undelivered. But absent from the debate is any discussion over reducing future health and pension costs, the biggest factors behind the U.S.’s longer-term debt burden.

Another political fight is looming over the raising the government’s $14.3-trillion borrowing limit. The Treasury Department said Tuesday that it will breach the debt ceiling between April 15 and May 31, a little later than its previous projection of April 5. Without approval from Congress to issue more debt, the U.S. could theoretically default on its existing obligations. Nevertheless, some Republicans are threatening to refuse the Treasury’s request for a higher borrowing limit.

For now, most investors appear to think politicians will work out their differences. The yield on 10-year Treasuries is about 3.5 per cent, a low rate by historical standards. Mr. Bernanke begged politicians to avoid squandering investors’ goodwill.

“Fortunately, the markets to this point seem to have a lot of confidence that we will address the problem,” Mr. Bernanke said. “I hope that we can meet that expectation.”