US Secretary of State Colin Powell sent a letter to Chinese Deputy Prime Ministers Zeng Peiyan and Wu Yi, urging the Chinese Government to reconsider its trade barrier.
Last year, China said that foreign Wi-Fi manufacturers would have to use Chinese encryption software if they wanted to trade in the country.
The Chinese initiative is set to begin in June this year.
China has also made moves to set its own technology standards for DVD players and mobile phones.
