Chinese Trade Negotiator Li, On Talks With U.S., Says We Had In-Depth, Candid Talks; Talked About Bilateral Tariffs Under New Circumstances; Talked About Possible Extension Of Tariff Suspensions, Other Matters; U.S. Talked About On Recent Tariff Adjustments; Chinese Side Voiced Concerns; Both Sides Agreed To Maintain Stability Of Tariff Levels; Discussed Mechanisms On Trade, Investment; China Raised Representations On Section 301 Probes; Opposes Unilateral Probes; Will Closely Monitor Progress Of Probes