Mossad chief David Barnea concluded his visit to Washington, where he held talks with senior US officials on the potential revival of the Iran nuclear deal.
Israeli media outlets cited the office of Israeli Prime Minister Yair Lapid, which said Mr Barnea showed American officials “sensitive intelligence material” on Iran.
Mr Barnea stressed that Israel would “not be able to stand idly by while Iran continues to deceive the world”, Mr Lapid's office said at the end of the three-day visit on Thursday.
The Mossad chief held meetings with CIA counterpart William Burns, FBI director Christopher Wray, National Security Adviser Jake Sullivan, US Defence Secretary Lloyd Austin, Chairman of the Joint Chiefs of Staff Mark Milley and senior officials at the State Department.
Before he embarked on the visit on Monday, the Israeli prime minister's office said Mr Barnea's visit would focus on tightening security and intelligence co-ordination with the US regarding the Iranian nuclear programme.
Mr Lapid has already voiced his opposition to the revival of the 2015 deal with Tehran. He repeated that what was signed in 2015 was “not a good deal” and that the one currently being formulated entailed “greater dangers”.
Mr Barnea's visit is considered by observers as the latest push by Israeli to sway western powers from a return to the 2015 deal with Tehran.
Israel has said a deal would enable the funding of Iran-supported militants while failing to prevent Tehran from developing a nuclear weapon — a goal Iran has always denied.
During his visit to Washington, US officials renewed their commitment to Israel’s security, Mr Lapid's office said.
“The Americans emphasised that they will not allow Iran to obtain a nuclear weapon and that they will continue to act in full co-operation with … Israel with regards to regional issues in the Middle East concerning the security of the state of Israel.”
The Times of Israel reported on Wednesday that top US officials had told Mr Lapid that a nuclear deal between Iran and world powers would not be signed in the foreseeable future.
In 2018, Donald Trump, US president at the time, unilaterally withdrew from the agreement designed to prevent Iran from developing a nuclear weapon.
His successor Joe Biden has sought to return to the deal. But over a year and a half of talks, negotiations have hit several obstacles, including Tehran's insistence that the International Atomic Energy Agency close its probes into uranium traces found at three undeclared sites before the nuclear pact is revived.
The US says that investigation must proceed unimpeded.