Microsoft Corp. said on Friday it may take decades to tackle software piracy in large emerging economies despite some recent progress and called on Asian governments to invest more in policing the practice.

We are realistic in recognizing that we have to work diligently over periods, that are really a decade or two, to make real progress in a number of these environments, Craig Mundie, Microsoft chief research and strategy officer, told Reuters.

Mundie, one of two successors to Microsoft founder Bill Gates next year, said progress had been made in countries like China and Vietnam in recent years to tackle software pirates, which cost the company billions of dollars each year.

However, he said more needed to be done to police the problem.

Most of the Asian countries have the laws, some of the regulations - they probably need tuning up - but the biggest weakness is very few of them have made the necessary investment on the enforcement side, Mundie said.

Microsoft has made progress in China where the piracy rate has dropped to 82 percent this year from 94 percent four years ago, he said. The piracy rate is a measure of the level of pirated software in the country. China President Hu Jintao last year pledged to crack down on software piracy.

Mundie was speaking to Reuters on the sidelines of a meeting of the 21 Asia Pacific leaders, some of whom have pledged flexibility in trade talks which have dragged for years.

As business people we certainly find it encouraging that the Doha Round could get completed and trade can go to the next level, said Mundie, who earlier addressed a forum of business leaders.

He said Microsoft expected to continue to grow its workforce and research and development capability in countries outside its dominant United States market, such as India.

The software company has been expanding beyond its Windows and office software businesses, saying Web services and consumer devices are key to the company's future. Its software products like the Windows operating system and Office productivity software account for most of the company's profit.