London (CNN Business) 1. Yuan watch: Investors are on high alert for China's yuan to fall to the symbolically important level of 7 to the US dollar. A move below that threshold, last breached during the 2008 financial crisis, could ripple through markets and further complicate trade talks between Washington and Beijing.

The yuan continued to fall Tuesday despite the United States moving to temporarily ease restrictions on Huawei, one of China's top tech firms. The Trump administration said Huawei could continue to do business with US suppliers for 90 days in order to maintain existing phones and networks.

But selling pressure remains. In trading outside China, one US dollar now buys roughly 6.94 yuan. In mainland China, where the yuan fluctuates around a reference rate set daily by the People's Bank of China, the currency stands at 6.91 to the dollar.

To many market watchers, it's a question of when, and not if, the yuan weakens below the 7 level in offshore trading, Jameel Ahmad, global head of currency strategy at FXTM, said in a note on Tuesday.

At that point, Beijing could either let its currency weaken further, helping Chinese exports to the United States but possibly angering the US government, or move to prop up the yuan. But such interference could also garner a negative political reaction, and also carries risks for the Chinese economy.