Premier Li Keqiang assured Western companies on Monday that China welcomes overseas firms competing in China's market under the principle of fairness.

His comments come as a string of antitrust investigations has prompted speculation that China no longer welcomes Western investors.

"China's door will only open wider. We are committed to taking our opening-up policy to a higher level and we advocate trade liberalization," Li said at the China Quality Conference, attended bydozens of foreign corporate leaders and foreign experts on quality management.