The US has ruled out any hasty withdrawal
Some 60% of people in 35 countries surveyed believe this is the case, against just 12% who think terrorist attacks have become less likely.
In most countries, more people think removing Saddam Hussein was a mistake than think it was the right decision.
Some 41,856 people were questioned in the poll for the BBC's World Service.
In 20 countries, there is overall support for US-led forces to withdraw from Iraq in the next few months.
Click below to see the poll's key results in graphs
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Only in nine of the remaining 15 countries do more people believe US-led forces should remain until the situation is stabilised. Six countries are divided.
The removal of Saddam Hussein in 2003 is seen as a mistake in 21 countries, compared with 11 countries where more people view it as the right decision. Three countries are divided.
"It's official. Citizens worldwide think Western leaders have made a fundamental mistake in their war on terror by invading Iraq," says Doug Miller, president of the international polling firm GlobeScan, which carried out the survey.
"Short of the Iraqi government asking them to stay longer, people think the troops should leave," he says.
The countries most eager for US coalition withdrawal are Argentina (80%), Egypt (76%), China (67%) and Brazil (67%). Those which favour troops staying for the time being are the US (58%), Afghanistan (58%), Australia (57%) and Great Britain (56%).
Iraqis divided
However, the picture would be very different should the new Iraqi government ask US-led forces to remain until the situation was stabilised.
In that case, there is support in 21 of 34 countries for the coalition to stay.
Iraqis themselves are sharply divided over whether US-led forces should leave, with 49% favouring their removal and 49% favouring them to remain.
Support for troops staying rises only slightly, to 53%, if the Iraqi government requests it.
Iraqis are the most convinced that the removal of Saddam Hussein was right, with 74% agreeing with the move.
US President George W Bush has ruled out any hasty withdrawal from Iraq, saying the decision to will be made by military commanders, and not under political pressure.
Sixty percent of respondents in an international survey conducted for the BBC World Service felt that the likelihood of terrorist attacks around the world has been increased by the war in Iraq.

The international polling firm ''GlobeScan'' conducted the survey, which polled 41,856 residents of 35 countries between October 2005 and February 2006. Participants were asked, "Has the war in Iraq increased, decreased or had no effect on the likelihood of terrorist attacks around the world?"

Fifteen percent felt that the likelihood or terrorism had decreased; 12 percent felt there had been no effect; and 13 percent did not answer.

Out of the 35 countries polled, only Mexico and Nigeria thought the invasion lessened the likelihood of terrorist attacks. By contrast, 85 percent of Chinese respondents said they felt the invasion increased the likelihood of terrorist attacks.

Other questions asked in the poll found that 45 percent of respondents felt removing Saddam Hussein from power was a mistake, compared to 36 percent who felt the removal was the right decision. The poll also found that results were split on whether the foreign troops should remain in Iraq until the country is stable: 35 percent said they believed the troops should stay, 32 percent felt the troops should pull out within a few months, and 13 percent thought that a pull-out should occur within a few months unless the government of Iraq requested them to stay.

"It's official. Citizens worldwide think Western leaders have made a fundamental mistake in their war on terror by invading Iraq," Doug Miller, president of ''GlobeScan'', said. "Short of the Iraqi government asking them to stay longer, people think the troops should leave," he said.

In the United States, the ''GlobeScan'' poll found that 55 percent thought chances of terror attacks were increased. In an unrelated poll conducted in the U.S. by ''CBS News'', only 36 percent of U.S. respondents thought "the war is going well," and that 30 percent felt "Bush was doing a good job of handling the conflict." This U.S. poll also found that only 18 percent held a favorable view of Vice-President Dick Cheney.

In a televised interview with Elizabeth Vargas of ABC's ''World News Tonight'' which aired last Tuesday, President Bush said, "If I worried about polls, I wouldn't be doing my job," on the topic of his low U.S. approval ratings. "I think the American people — I know the American people want somebody to stand on principle, make decisions and stand by them and lead this world toward a more peaceful tomorrow, and I strongly believe we're doing that," he said.  

"I've got ample political capital and I'm using it to spread freedom and to protect the American people, plus we've got a strong agenda to keep this economy growing." President Bush also said that Iraqis must choose between "chaos or unity."