The United States' largest trading partner may be in a recession, but the U.S. doesn't seem to be worried.

Canada's economy has likely shrunk for two straight quarters, meeting the most common definition of a recession.

But even as top policymakers have been repeatedly quizzed about the possible threats to the U.S. economy from a Greek default or Chinese stock market collapse, little attention has been given to the likelihood that the country's top trading partner may have entered a recession.

The topic did not come up once during Federal Reserve Chairwoman Janet Yellen's two days of testimony on Capitol Hill this week, even though she did mention Greece and China. Nor have Treasury Secretary Jack Lew or other officials mentioned problems stemming from Canada's struggles.

The Bank of Canada on Wednesday projected that the country's economy would shrink at a 0.5 percent annual pace in the second quarter, following a 0.6 percent contraction in the first quarter.

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Stephen Poloz, governor of the central bank, declined to say that the country was experiencing a recession in a press conference, saying that the distinction was not helpful. He blamed the slowdown on falling oil prices hurting Canadian producers, slowing commodity exports to China, and faltering non-commodity exports as well. The central bank cut its main interest rate target to 0.5 percent in an effort to stave off a deep downturn.

But the country accounts for nearly 16 percent of U.S. total trade and nearly a fifth of total exports.

Some small signs of trouble with commerce across the Northern border have already cropped up. In the Fed's "Beige Book," a summary of economic conditions faced by businesses in different districts, Minneapolis reported fewer Canadian shoppers because of the strength of the U.S. dollar relative to Canadian currency.

But Canada's problems, for now, may be concentrated in energy-producing industries. Furthermore, the unemployment rate, at 6.8 percent in June, is down, if only by 0.2 percentage points, from a year earlier.

"It's certainly not clear that we're in a recession, and it might not even be anything more than sort of a very targeted, of the oil industry, fall," said Jeremy Kronick, a policy analyst at the C.D. Howe Institute, a Toronto think tank that has tried to develop a better gauge of recessions.

Kronick suggested that Canada's first-half troubles are connected to the U.S. winter economic contraction, which has been partially blamed on harsh winter weather, a strike at West Coast ports and other one-time events.

Federal Reserve and private-sector economists project that U.S. growth will resume in the second half of the year. The Bank of Canada expects the same for Canada.

"I would expect that as long as the U.S. rebound occurs, our numbers should be OK," Kronick said.

Although the Fed began saying this year that it would take international developments into account in moving toward monetary policy tightening, neither it nor the Treasury has expressed serious concern about fallout for the U.S. economy from Canada, or from Greece or China.

In her June press conference, Yellen said "the United States has very limited direct exposure to Greece, either through trade or financial channels. But to the extent that there are impacts on the euro-area economy or on global financial markets, there would undoubtedly be spillovers to the United States that would affect our outlook as well."

At the Brookings Institution in Washington, Treasury Secretary Jack Lew said last week that he doesn't "see any immediate threat to the continued growth in the U.S. economy. We keep our eye on developments around the world constantly."