Wikileaks on Friday posted documents they allege are proof that the US government spied on Japanese government officials and Japanese companies.

The website posted what appear to be documents from the US National Security Agency that possibly dated back to as early as 2006, including a list of 35 Japanese telephone numbers as potential intercept targets.

The list includes phone numbers from the Japanese Cabinet office, car manufacturer Mitsubishi, as well as Trade Minister Yoichi Miyazawa and Bank of Japan governor Haruhiko Kuroda.

"The reports demonstrate the depth of US surveillance of the Japanese government, indicating that intelligence was gathered and processed from numerous Japanese government ministries and offices," WikiLeaks said in a statement. "The documents demonstrate intimate knowledge of internal Japanese deliberations."

Questions of trade and climate

Four of the posted documents were marked "top secret," and at least three documents dealt with Japan's position on climate change. One of these was marked for sharing with Australia, Canada, the UK and New Zealand at the 2008 G8 summit, which Japan hosted.

Two other documents deal with issues of US-Japan agricultural trade, including "content of a confidential prime ministerial briefing that took place at (Prime Minister) Shinzo Abe's official residence," Wikileaks said. "We now know that the United States heard everything and read everything, and was passing around the deliberations of Japanese leadership to Australia, Canada, New Zealand and the UK."

"In these documents we see the Japanese government worrying in private about how much or how little to tell the United States, in order to prevent undermining of its climate change proposal or its diplomatic relationship," WikiLeaks Editor-in-Chief Julian Assange said in a statement.

While close allies, the United States and Japan have struggled to come to a consensus over their auto manufacturing sectors and Japan's desire to protect agricultural products.

Ongoing negotiations

A spokesman for the Japanese Foreign Ministry said Japan was in contact with the US regarding the issue of "information collection" but did not elaborate. "Japan will continue to employ all the necessary measures to protect [its] information," he told reporters.

Spokespeople for Mitsubishi and the Mitsui Corporation chose not to comment the WikiLeaks documents. The US embassy in Tokyo also said it was aware of the leak but did not comment further.

Representatives from both the United States and Japan are in Hawaii this week for high-profile regarding an Asia-Pacific free-trade bloc that would make up 40 percent of the world's economy. If they reach a deal, it would be the most ambitious trade agreement in decades.

WikiLeaks had previously released similar documents showing the US was spying on Germany, France and Brazil.

mes/sms (AFP, AP)