Four trade associations representing US importers have reacted angrily to comments from a senior American trade official who says the US may impose limits on Chinese apparel imports if manufacturers can prove that such restrictions are necessary.

In a letter to Grant Aldonas, the under secretary of commerce for international trade, the trade groups register their "strong objections to consideration of China textile safeguard petitions on products that remain under quota through the end of 2004."

The letter argues the petitions would be based on assumptions and conjecture rather than facts, "which is not permitted under the safeguard mechanism."

It is more usual practice to limit imports after they have damaged a local industry.

The trade groups also say the consideration of any petitions goes against assurances "that the Administration would manage the transition to a quota-free environment with minimal disruption and harm to our sector."

Despite warnings that the Chinese government might challenge the American policy before the World Trade Organisation, American manufacturers are expected to start filing requests for import restrictions as early as this week.