Japan will take "concrete steps" to reduce its oil dependency on Iran, its finance minister has announced.

日本财政部长宣布，将采取“具体步骤”减少对伊朗石油的依靠。

The comments from Jun Azumi came after he met US Treasury¹ Secretary Timothy Geithner in Tokyo.

Mr Geithner is seeking backing from China and Japan for stricter sanctions on Iran's oil industry in a bid to curb² Tehran's nuclear ambitions.

On Wednesday he raised the issue with Chinese leaders in Beijing, but did not get the same support.

"In the past five years, we have reduced... the amount of oil imported (from Iran)," Mr Azumi said during a joint³ press conference with Mr Geithner.

"We wish to take planned and concrete steps to further reduce this share, which now stands at 10%."

Japan is the second biggest customer for Iranian oil, and has already urged Gulf⁴ Arab countries to increase their exports to make up any shortfall.

The supplies are badly needed as it is using increasing amounts of thermal⁵ power to generate electricity because of the nuclear crisis at Fukushima.

Mr Geithner welcomed the Japanese response.

''We are working very closely with Europe and Japan and allies around the world to substantially increase the amount of pressure we bring on Iran,'' he said.

"We very much appreciate the support Japan has provided standing⁶ with us and the international community in support of this very important strategic objective."

Mr Geithner's visit to East Asia comes amid international tension after the UN's nuclear watchdog said Iran had begun enriching uranium to a higher grade than is needed for power generation.

The US has accused Iran of "blatant⁷（喧嚣的，公然的） disregard for its responsibilities".

On New Year's eve, US President Barack Obama authorised a law imposing⁸ sanctions on financial institutions dealing⁹ with Iran's central bank, which is responsible for processing most oil purchases.

In Beijing, Mr Geithner met Premier¹⁰ Wen Jiabao, Vice¹¹-President Xi Jinping and Vice-Premier Li Keqiang on Wednesday and counterpart Vice Premier Wang Qishan on Tuesday night.

Amid escalating¹² tensions over Iran's nuclear programme, an Iranian nuclear scientist was killed by a magnet bomb fixed¹³ to his car by a motorcyclist. Tehran has blamed Israel for the attack.

Iran says its nuclear programme is for power generation purposes only.