The Tokyo stock exchange's Nikkei 225 index in Tokyo was around zero at lunchtime, while the broader Topix index had risen 0.3 percent.
In Hong Kong, the Hang Seng index was instead down 0.9 percent.
The composite indexes in Shanghai and Shenzhen had both climbed around 0.2 percent.
Investors have to relate to the US tariff threats. President Donald Trump has given conflicting messages about whether the extended pause - until August 1 - for general tariffs is negotiable or not.
Now, the Trump administration is also considering 50 percent tariffs on imports of copper and, in the slightly longer term, tariffs of up to 200 percent on medicines.
In China, new monthly statistics have been presented. Consumer prices rose in June by 0.1 percent in annual terms, according to the country's national statistical office. This is an unexpected trend break after prices have fallen for four months in a row.
The producer price index fell simultaneously by 3.6 percent in June, the largest decline in nearly two years, which means that prices have been falling for 33 months in a row, according to Bloomberg.
