British Prime Minister Theresa May and Saudi Crown Prince Mohammed bin Salman, at the end of the latter's state visit to London on Friday, mutually vowed to "disarm Hezbollah and confront its destabilizing role" and weaken Iran's regional influence.
According to the Saudi Press Agency, both countries agreed to help the Lebanese government consolidate its control over southern Lebanon and said Iran must "abide by the principles of good neighborliness and noninterference in the internal affairs of countries."
Upon his arrival in the United Kingdom last Wednesday, the Saudi crown prince was greeted by Queen Elizabeth II.
Also Friday, Britain approved the $6.9 billion sale of 58 highly advanced Typhoon fighter jets to Saudi Arabia, disregarding calls to boycott the kingdom over its role in Yemen's civil war.
Saudi Arabia already has 72 Typhoon jets.
Britain and Saudi Arabia also signed commercial deals worth more than $2 billion.
At the start of the trip, the countries set themselves a $90 billion trade and investment target for the coming years, with London looking for new post-Brexit markets for its services sector, and Crown Prince Mohammed seeking to convince wary investors his country is a tolerant and modernizing place.
Critics say Britain has been slow to condemn rights abuses by Saudi Arabia, a key regional ally and major purchaser of U.K.-made weapons.
A Saudi-led coalition has been battling Iran-allied rebels in Yemen since 2015 in a war that has killed more than 10,000 people and driven the Arab world's poorest country to the brink of famine. The kingdom faces wide international criticism for its airstrikes killing civilians and striking markets, hospitals and other civilian targets.
Campaigners against the war rallied near Parliament and held a protest outside the gates of Downing Street.
Asked by Labour Party leader Jeremy Corbyn whether she would condemn Saudi Arabia's "shocking abuse of human rights," May defended Britain's close ties with the authoritarian kingdom.
"The link with Saudi Arabia we have is historic, it is an important one, and it has saved the lives of potentially hundreds of people in this country" due to anti-terrorism cooperation, she told MPs.
"Their involvement in Yemen came at the request of the legitimate government of the Yemen, it is backed by the U.N. Security Council, and as such we support it," she said.
Meanwhile, a former prime minister of Qatar and a senior adviser to Saudi King Salman exchanged Twitter barbs over the weekend, with the Qatari accusing Saudi Arabia of "neglecting the Palestinian issue for the sake of normalization with Israel."
King Salman's adviser tweeted in response: "You [Qatar] are the Trojan horse in the Arab nation and those who forced the girls of Qatar to greet [former Israeli President] Shimon Peres with flowers in Doha – where is your shame?"
