Israel refuses to confirm it possesses a nuclear arsenal but it is widely considered to be the Middle East's only nuclear power.

A report by the Vienna-based watchdog made public Friday says agency chief Yukiya Amano "invited Israel to consider to accede" to the treaty during a low-key visit to the country last month.

The report also contained a July 26 letter from Israeli Foreign Minister Avigdor Liberman that pointed the finger at Iran and Syria as the region's "real proliferation challenges."