Trade talks between the world’s largest economies began on Monday and have extended into Tuesday. 

Investors are hoping that the talks will spur further deescalation in a bitter trade tariff exchange between the U.S. and China, after they agreed in May to temporarily slash their respective tariffs. 

Focus this time round is on China’s restriction of rare earth minerals, which have threatened to greatly disrupt global supplies, as well U.S. restrictions on chip exports to China. 

Trump had authorized his trade negotiators to walk back recent restrictions on chip and tech exports to help move along negotiations, the Wall Street Journal reported. Other reports showed that Trump was actively considering ending the restrictions to win favor with China, with Beijing’s restrictions on rare earth exports being a major point of contention. 

Trump said on Monday that the talks were going well, and that he was “only getting good reports” from his team in London. 

However, optimism is starting to drain amid speculation that Chinese officials aren’t satisfied with the talks, and it doesn’t take much to put traders on edge giving the previous frosty relationship between the two sides.