Israeli Prime Minister Benjamin Netanyahu met Prime Minister Theresa May in London on Monday for talks he hopes will focus on Iranian weapons, and not Israeli settlements.
Britain, meanwhile, wants the talks at 10 Downing St. to discuss boosting trade ties between the two countries.
Netanyahu told reporters in Jerusalem on Sunday that he would "emphasize the need for a common front against Iran's defiant aggression which has raised its head in recent days." Iran fired a ballistic missile last week.
Iran and Israel are bitter enemies. Netanyahu vehemently opposes the 2015 international agreement that imposed curbs on Tehran's nuclear program in exchange for lifting sanctions. Britain backs the deal, which May has called "vital."
President Donald Trump, with whom May's government wants close ties, is also a critic of the Iran deal.
The Trump administration is also perceived as sympathetic to Israeli settlements on occupied Palestinian land, an issue that caused friction between Netanyahu and former President Barack Obama.
The Palestinians claim the West Bank and east Jerusalem, captured by Israel in the 1967 Mideast war, as parts of a future state. They say the settlements, home to 600,000 Israelis, are making it increasingly impossible to partition the land into two states — a position that has wide international backing.
May is under pressure to condemn Israeli settlement-building. The prime minister's office said May would raise Britain's longstanding concerns that the settlements undermine the peace process, although it is expected to form only a small part of the meeting.
Britain wants the talks to focus on trade. The U.K. is seeking to bolster trade relations outside the European Union once it leaves the 28-nation bloc.