OTTAWA - The No. 1 recipient of Canadian taxpayers' foreign-aid dollars is the second-most corrupt country in the world, a new report says.

Afghanistan tied with the military dictatorship in Myanmar as the second-most corrupt country on the planet, according to the yearly audit by the Berlin-based group Transparency International. Somalia won the dubious distinction as most corrupt on the organization's annual Corruption Perceptions Index.

On the least-corrupt scale, Canada inched up to sixth from eighth from a year earlier in the ranking of 178 countries. Denmark, New Zealand and Singapore topped the list as the countries with the most virtuous public sectors.

Through 2011, Canada has earmarked $1.9 billion in development assistance to Afghanistan, the single-largest recipient of its foreign-aid spending.

Western concerns about corruption in Afghanistan have been an issue for years, and they were revived this week when President Hamid Karzai admitted his government receives bags of cash from Iran totalling in the millions of dollars.

"Unstable governments with a history of conflict continue to dominate the bottom rungs of the (index)," said Huguette Labelle, the organization's chair.

"Corruption nourishes poverty, it seeds violence, it destabilizes countries," added Labelle, a retired federal public servant who once headed the Canadian International Development Agency.

Fighting corruption needs to be made a central element of poverty reduction, she said.

Labelle said three-quarters of the world's countries have a serious problem with corruption, including members of the G20, which is trying to guide recovery from the global economic crisis.

"With governments committing huge funds for the world's most pressing problems, including the stabilization of financial markets, climate-change mitigation and poverty reduction, corruption remains a serious obstacle and a cause for concern," said Labelle.

"The vital issue remains enforcement, without which all the laws in the world will be of little value."

Labelle said it was good that the G20 has made a commitment to transparency ahead of its November summit in South Korea.

Corruption scores declined among a number of higher-income countries "rattled by the financial crisis," she said.

The United States was singled out for its decline to 22nd from 19th place, while Italy and Greece also fell, to 67th and 78th respectively.

The corruption assessment is a composite index that drew upon 13 different expert and business surveys from January 2009 to September 2010. It measures the "abuse of entrusted power for private gain" in the public sectors of countries.

The index assigns countries a rating from 0 to 10. The highest marks went to the three first-place finishers -- Denmark, New Zealand and Singapore -- each of which scored 9.3.