Concerted action is needed to prevent the Middle East "disintegrating" under the threat of militant Islamists, Benjamin Netanyahu said as he arrived at Downing Street for talks with Prime Minister David Cameron.
Discussions are set to be dominated by the crisis in Syria and developments in Iran, notably the nuclear deal brokered by the UK and Western allies with Tehran which is bitterly opposed by the Israeli premier.
His arrival was not greeted with a repeat of the vocal protests seen outside the gates of Number 10 on the eve of the visit. when campaigners demanding his arrest for alleged war crimes in Gaza clashed with pro-Israel activists.
Both sides in Gaza declared victory after a ceasefire was secured to halt the seven-week war that left more than 2,000 Palestinians dead and tens of thousands homeless, and devastated entire neighbourhoods in the blockaded territory.
Although a petition calling for Mr Netanyahu to be arrested secured enough support to be considered for a debate in Parliament, the bid was rejected earlier this week because "visiting heads of foreign governments, such as Prime Minister Netanyahu, have immunity from legal process, and cannot be arrested or detained".
In opening remarks, Mr Cameron said the UK "remains staunch in our defence of Israel's right to exist and to defend itself".
Mr Netanyahu told him: "The Middle East is disintegrating under the twin forces of militant Islam - militant Sunnis led by Isis and militant Shi-ites led by Iran.
"I believe that we can co-operate in practical ways to roll back the tide of militant Islam both in the Middle East and in Africa."
He repeated his recent declaration that he was "ready to resume direct negotiations with the Palestinians with no conditions whatsoever to entering negotiations ... immediately".
Earlier this year Iran struck a deal after a decade of negotiations with world powers over its nuclear programme, with some sanctions being lifted in return for allowing inspections.
But Mr Netanyahu remains angry about the accord which he claims will embolden Iran's ambitions, and is reportedly lobbying the US Congress to block the deal.