Wen Jiabao has agreed to soften curbs on some Japanese agricultural products introduced amid safety fears over the crisis at the Daiichi nuclear plant.

The decision by the Chinese premier was a gesture of goodwill at a trilateral summit in Tokyo between Naoto Kan, Japan’s prime minister, Lee Myung-bak, South Korean president, and Mr Wen.

But the relative success of Mr Kan’s weekend talks came as he faced more pressure over his government’s handling of the nuclear crisis at Tokyo Electric Power’s nuclear reactor.

Yomiuri Shimbun, Japan’s biggest daily, and the Kyodo news agency said Mr Kan had expressed concerns that injections of seawater into the stricken plant after it was damaged by the earthquake and tsunami of March 11 might have caused “re-criticality”, causing delays of nearly an hour in the attempt to cool the Number one reactor.

Re-criticality is a new, and uncontrolled, fit of nuclear fission.

Mr Kan’s concern arose from a discussion with Haruki Madarame, chairman of the Nuclear Safety Commission, the Yomiuri said. However, on Sunday, Mr Kan’s government waved aside the notion that any order to stop injecting seawater had been given.

Mr Kan’s actions at what was a critical time are likely be the subject of much parliamentary scrutiny this week, adding to fierce criticism the prime minister is facing for his handling of the crisis.

Mr Wen and Mr Lee gave Mr Kan some relief from his domestic political friction as the three leaders travelled to Fukushima, the capital of the prefecture where Tepco’s Daiichi plant is located. Mr Wen and Mr Lee sampled locally grown cherries and visited an evacuation centre in a sign of support for their neighbour.

The weekend talks were believed to have been co- operative and avoided contentious subjects such as disputes over territories.

China agreed to ease restrictions on the import of agricultural products from two prefectures far from the stricken Fukushima plant, leaving 10 other prefectures, many also far from Fukushima, with import bans. Mr Wen also agreed to cancel requirements for radiation inspection certificates for agricultural products from the other prefectures, except for dairy, marine and vegetable products.