CHINA has given assurances that it will not discriminate against any country in trade and economics because of political friction. The pledge apparently means Beijing will not retaliate against British business because of the dispute over Hong Kong. China has also agreed to discuss what amounts to self-imposed export quotas to prevent Chinese goods from flooding the world market as a condition for joining the General Agreement on Tariffs and Trade (GATT). The assurances were given to Sir Leon Brittan, European Commissioner for external trade relations, during meetings with China's Minister of Foreign Trade and Economic Relations, Wu Yi, and other officials. Sir Leon said yesterday that Chinese officials made the non-discrimination commitment three times following a press conference on Monday in which Ms Wu repeated her Government's position that the dispute over Hong Kong could not but affect trade and economic relations with Britain. The European Commissioner had warned that the entire European Union (EU) would react strongly to discrimination against any of its member states. Sir Leon said yesterday that Chinese officials gave ''unequivocal assurances that there will be no discrimination against any individual member state on political grounds''. He said they acknowledged that non-discrimination was not only the foundation of China's agreement with the EU, but was fundamental to its GATT bid. He asked China to treat other countries in the same way it demanded to be treated by the world community. ''The concept of discrimination is not a difficult one. It may be difficult to prove in a particular case . . . but I hope it will not arise,'' Sir Leon said.