Britain's Prince William arrives to the birthday party of Britain's Queen Elizabeth, at the residence of British Ambassador to Jordan Edward Oakden, in Amman, Jordan, June 24, 2018.

Britain's Prince William and Jordan's Crown Prince Hussein bin Abdullah II review the honour guard in Amman, Jordan, June 24, 2018.

Jordanian honour guard prepares for the arrival of Britain's Prince William in Amman, Jordan, June 24, 2018.

Britain's Prince William and Jordan's Crown Prince Hussein during their visit to the Crown Prince Foundation in Amman, Jordan, June 24, 2018. Jordanian Royal Palace/Handout via REUTERS ATTENTION EDITORS - THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY.

Britain's Prince William leaves the plane as he arrives in Amman, Jordan, June 24, 2018.

Britain's Prince William attends the birthday party of Britain's Queen Elizabeth, at the residence of British Ambassador to Jordan Edward Oakden, in Amman, Jordan, June 24, 2018.

Britain's Prince William and Jordan's Crown Prince Hussein during their visit to the Crown Prince Foundation in Amman, Jordan, June 24, 2018. Jordanian Royal Palace/Handout via REUTERS ATTENTION EDITORS - THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY.

Britain's Prince William is welcomed by Jordan's Crown Prince Hussein bin Abdullah II in Amman, Jordan, June 24, 2018.

Britain's Prince William and Jordan's Crown Prince Hussein bin Abdullah II review the honour guard in Amman, Jordan, June 24, 2018. REUTERS/Muhammad Hamed

Britain's Prince William gestures as he attends the birthday party of Britain's Queen Elizabeth, at the residence of British Ambassador to Jordan Edward Oakden, in Amman, Jordan, June 24, 2018.

Britain's Prince William and Jordan's Crown Prince Hussein during their visit to the Crown Prince Foundation in Amman, Jordan, June 24, 2018. Jordanian Royal Palace/Handout via REUTERS ATTENTION EDITORS - THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY.