An increasing number of Russians have become disillusioned with President Vladimir Putin's ability to improve the economy and curb rampant corruption, while support for his foreign policy has remained strong, according to a poll released Tuesday.

A Pew Research Center survey said 40 percent disapprove of the way the Russian leader is handling the economy, compared to 23 percent two years ago. Separately, 45 percent of those polled disapprove of how he is dealing with corruption, compared to 29 percent two years ago.

The nationwide poll of over 1,000 people had an error margin of four percentage points and was conducted in February-April.

Russia's economy has been hit by a combination of flagging energy prices and Western sanctions over Moscow's annexation of Ukraine's Crimea and support for pro-Russian insurgents in eastern Ukraine.

Tens of thousands protested against corruption across Russia's 11 time zones earlier this month, a widespread show of discontent that cast a challenge to the Kremlin.

Putin's annual call-in show last week also highlighted Russians' frustration with falling living standards and local officials' indifference to their problems. Many of the callers complained of low pay, crumbling health care and other social problems, while Putin sought to project a more positive view by citing official statistics signaling that the economy is on the way to recovery after a two-year recession.

While a large share of Russians have a pessimistic view of domestic issues, the Pew survey indicated public support for Putin's foreign policy remains strong.

In the poll, 87 percent of respondents said they have confidence in Putin to do the right thing regarding world affairs. Most believe Russia's global clout has risen, with a 59 percent majority believing the country now plays a more important role in the world than it did a decade ago.

A 46 percent plurality think Russia should maintain its military involvement in Syria at the current level, while 34 percent believe Moscow should decrease its scale and 11 percent would welcome a stronger Russian engagement there.

Only 25 percent see ensuring Syrian President Bashar Assad's hold on power as a top priority, compared to limiting civilian casualties and defeating extremist groups, which are seen as top priorities by 72 percent and 64 percent of those polled, respectively.