China's biggest search engine, Baidu Inc, plans to provide free downloads of copyrighted music from next week. The move comes as a response to increasing criticism of its involvement in copyright infringement.

The new service, Baidu Ting, will see the search giant in head-to-head competition with its rival Google Inc, which has invested in Top100.cn, a website offering legal music downloads.

"Copyrighted music will be the direction of Baidu's music business in the future, and our music-search service will also be based on legal content," said Catherine Leung, general manager of the company's digital entertainment business.

However, she said Baidu will not shut down Baidu MP3, its music-search service that enables users to search, stream and download music free of charge. The service has long been the target of criticism from the recorded music industry because it directs users to content that infringes copyright.

The International Intellectual Property Alliance (IIPA), which represents the United States' copyright industry groups, testified at a US Congress hearing on Wednesday that Baidu had "serious infringement problems".

This was part of the United States' efforts to urge China to promote intellectual property protection ahead of the forthcoming Strategic and Economic Dialogue between the two nations.

An estimated 50 percent of all illegal music downloads in China take place through Baidu, according to an IIPA report.

However, Leung, who was general manager of Universal Music Group's China operations before she joined Baidu in 2008, said the company is open to all kinds of cooperation with music companies for their mutual benefit.

Google has been providing a legal music search service since 2009. The company has entered into partnership with Top100.cn, a Chinese music website co-founded by the basketball star Yao Ming, to provide copyrighted songs. Google is still running the service, despite shutting down others last year.

Leung said there are about 500,000 copyrighted songs on Baidu Ting, and the figure is expected to exceed 1 million within one or two months. In the summer, the company will offer the Baidu Ting client software for iPhones and mobile phones operating on the Android system, according to Leung.

The service, which is undergoing testing and is only open to a limited number of users at present, plans to generate revenue through subscriptions and advertising, among other methods.

Baidu took 75.8 percent of the country's search market in the first quarter of this year, followed by Google with 19.2 percent, according to Analysys International. Google has seen a decline in its market share since redirecting its mainland traffic to Hong Kong.