JERUSALEM: The head of Israel's intelligence service, Tamir Pardo, is in Washington for talks about a possible attack on Iran's nuclear installations, Israeli media reported on Tuesday.
The visit by the Mossad chief, which would usually be conducted in secret, was accidentally revealed by US Senate Intelligence Committee Chairwoman Dianne Feinstein at a committee hearing, Israel's Channel Two TV station reported.
The hearing was broadcast live by US television.
Feinstein said she had spoken with Pardo, who also met the CIA director David Petraeus, Channel Two said, adding that the Mossad chief had mentioned the possibility of unilateral Israeli action against Iran.
Israeli officials have sent conflicting messages about the option of pre-emptive military strikes on Iran's nuclear facilities.
President Shimon Peres on Tuesday reaffirmed that "no option should be excluded against the programme of Iran, which seeks to acquire weapons of mass destruction."
"The regime of the ayatollahs is the most corrupt in the world, from a moral point of view," Peres told a conference in Herzliya, near Tel Aviv.
The United States and other Western governments accuse Iran of seeking an atomic weapons capability, something Tehran has always denied.
Israeli leaders fear a nuclear-armed Iran would pose an existential threat to the Jewish state, which has the Middle East's sole if undeclared nuclear arsenal.
Earlier this month, Iran's supreme leader, Ayatollah Ali Khamenei, accused the CIA and the Mossad of being behind the assassination of one of its top nuclear scientists, who was killed by a magnetic bomb fixed to his car in Tehran.
Three other scientists, two of them involved in Iran's nuclear programme, have been murdered in similar circumstances over the past two years, with Israel widely seen as the prime suspect.
Some Israeli media reported in October last year that the option of pre-emptive air strikes on Iran was opposed by the country's intelligence services but favoured by Prime Minister Benjamin Netanyahu and Defence Minister Ehud Barak.