Prime Minister Rishi Sunak has met Benjamin Netanyahu at Downing Street as the Israeli leader faces domestic turmoil over judicial reforms.
Mr Sunak greeted Mr Netanyahu outside No 10 before talks over security and the threat from Iran.
Mr Netanyahu will also meet Home Secretary Suella Braverman on his one-day visit.
Hundreds of protesters gathered at the gates of Downing Street to demonstrate against the Israeli PM's policies.
There was a cacophony, including shouts of "shame" and "traitor", as Mr Netanyahu made the short walk from his convoy to the steps of Number 10.
A planned photo opportunity for media at the start of the talks was cancelled, and there was no joint statement.
The visit comes at a time of political turmoil in Israel, with the country gripped by months of some of the biggest demonstrations in its history.
Mr Netanyahu has defied calls to scrap a shake-up of the legal system, amid warnings the crisis is not only causing social upheaval but could harm Israel's security.
Growing numbers of military reservists are refusing to serve in protest.
Thursday saw tens of thousands of Israelis take to the streets across the country, in scenes which have been repeated weekly and escalated since the start of the year.
