The opening dinner Wednesday night of the two-day, US-organised conference marked "a historical turning point," Netanyahu told reporters.

"In a room of some 60 foreign ministers representative of dozens of governments, an Israeli prime minister and the foreign ministers of the leading Arab countries stood together and spoke with unusual force, clarity and unity against the common threat of the Iranian regime," he said.

"I think this marks a change and important understanding of what threatens our future, what we need to do to secure it, and the possibility that cooperation will extend beyond security in every realm of life."

At the opening dinner at Warsaw's Royal Castle, officials said that Netanyahu spoke around the same table as senior officials of Saudi Arabia, the United Arab Emirates and Bahrain -- none of which have relations with Israel but all of which share Netanyahu's hawkish stance on Iran.

Israel only has diplomatic relations with two Arab states, neighbouring Egypt and Jordan.

Netanyahu also met one-on-one in Warsaw with Foreign Minister Yusuf bin Alawi bin Abdullah of Oman, where he travelled late last year. Oman has sought friendly relations with all regional players including Iran.

US Vice President Mike Pence and US Secretary of State Mike Pompeo are both attending the conference co-hosted with Poland, which is eager for strong ties with Washington in the face of the threat of Russia.

But most European powers are sending low-level representation, wary of the hawkish line on Iran by President Donald Trump who withdrew from an international accord on curbing Tehran's nuclear programme.