With Hong Kong and Seoul markets closed for Buddha’s birthday, the benchmark Shanghai Composite Index opened up 0.33 percent at 4,126.
The Shenzhen Component Index opened 0.76 percent higher at 15,716 while the ChiNext Index was up 0.93 percent at 3,974.
Hopes of a deal to reopen the Strait of Hormuz also lifted market sentiment.
In Tokyo, the Nikkei surged 1,819 points, or 2.87 percent, to go past 65,158 at one stage before midday after opening 319 points up at 63,658 to breach the 65,000 mark for the first time.
The Topix was up 45 points, or 1.16 percent, at 3,937 at one stage near midday.
The news of a potential US-Iranian deal sparked a drop in oil prices along with gains in Japanese government bonds and the yen, adding to signs of improving risk sentiment, said Maki Sawada, an equities strategist at Nomura Securities.
“Even if an agreement is reached, there remains uncertainty regarding whether it will be adhered to, as the Iranian government may not be united on the issue,” Sawada said.
“The 65,000 mark is a psychological milestone, so reaching this level has led to some caution and selling pressure at such a high price range.” (Agencies & Xinhua)
