Asian shares are mixed as investors keep an eye on China

Asian shares were mixed on Tuesday as investors kept a wary eye on China-U.S. trade talks that could have a huge impact on the global economy.

U.S. futures were flat and oil prices rose.

A second day of talks was planned after U.S. and Chinese officials met in London on Monday for negotiations over various issues. The hope is that they can eventually reach a deal to reduce painfully high tariffs against each other. Most of the tariff hikes imposed since U.S. President Donald Trump escalated his trade war are paused to allow trade in everything from tiny tech gadgets to enormous machinery to continue.

In Asian trading, Tokyo's Nikkei 225 gained 0.2% to 38,169.76, giving up early gains, while the Kospi in South Korea rose 0.3% to 2,866.66.

Hong Kong's Hang Seng reversed its early advance