The new Crown Prince of Saudi Arabia is to visit the UK next month, Downing Street has confirmed.
It will be Mohammed bin Salman's first trip to Britain since taking on wide-ranging powers in the Gulf kingdom on his appointment last June.
Number 10 said it would "usher in new era in bilateral relations", providing an opportunity to enhance co-operation on terrorism, the conflict in Yemen and regional issues including Iraq and Syria, as well as to boost trade links.
But the trip, beginning on March 7, is certain to be marked by protests by campaigners against Saudi Arabia's role in the Yemen conflict, its domestic human rights record and its position as a major player in the international arms trade.
Ministers are likely to use the opportunity to press for the state-owned Saudi Aramco oil company to choose London for its mooted stock market flotation over bids from New York, Hong Kong and Tokyo.
Prime Minister Theresa May said: "The partnership between the UK and Saudi Arabia already helps make both of our countries safer, through intelligence-sharing which has saved British lives, and more prosperous, with thousands of jobs created in the UK and substantial opportunities for British companies in Saudi Arabia.
"The visit of the Crown Prince will establish the platform for that relationship to become even stronger."
Mrs May welcomed reforms introduced by Prince Mohammed to grant women rights to drive and attend sporting events, as well as to allow cinemas to open in the fiercely traditionalist desert nation.
"Saudi Arabia is changing," she said.
"We have seen recent decisions to allow women to drive from June this year, a target for women to make up one third of the Saudi workforce by 2030, and a move to develop sectors such as health, education, infrastructure, recreation and tourism.
"These are all sectors where the UK leads the world and where there are new opportunities to work together."
Mrs May insisted she would not shy away from tackling difficult issues in face-to-face talks with the Crown Prince.
"Our strong relationship with Saudi Arabia enables us to talk frankly and constructively about issues where we both have concerns, such as regional security and the conflict and humanitarian situation in Yemen," she said.
Crown Prince Mohammed, 32, has made a series of dramatic moves to establish his authority in Saudi Arabia following his elevation last year by his 79-year-old father King Salman.
In November, more than 40 princes and government ministers were arrested over alleged corruption, and this week he sacked some of the generals leading the long-running campaign in Yemen.