British RAF planes have started evacuation flights from Israel while officials have told UK citizens in Gaza to "be ready" if the Rafah crossing opens, the Foreign Office said. Foreign Secretary James Cleverly on Sunday said he was trying to arrange the reopening of the Rafah crossing – the only passage in and out of the Gaza Strip not controlled by Israel, which has been closed since Tuesday – but the situation remained “very, very difficult”. The first three flights carrying Britons fleeing the conflict arrived in Cyprus and the UK on Sunday. There are an estimated 60,000 British citizens in Israel and Gaza, including the parents-in-law of Scotland’s First Minister Humza Yousaf. The Foreign Office has told citizens in Gaza to prepare for the Rafah crossing opening and further government flights are planned with specialist teams deployed to support vulnerable people. “I've been speaking with the Egyptian authorities, with the Israeli authorities, and also with other leading political voices in the region to try to facilitate the opening of a Rafa crossing from Southern Gaza into Egypt,” Mr Cleverly told the BBC. “That's not been opened yet and these are incredibly difficult conversations, very sensitive conversations, but we are seeking to provide support to those British nationals who are seeking to leave Gaza and we are looking to facilitate humanitarian support for the people of Gaza. "It is very, very difficult. At the moment we have not been successful in getting the Rafah crossing opened.” One of the planes used on Sunday was an RAF A400M Atlas transport aircraft, last used in the evacuation of citizens from Sudan this year and also from Kabul in 2021. It is expected similar planes will be on standby to fly into the region and land at rugged airstrips to pick up British citizens in the coming days. The Rafah crossing lies on Gaza’s southern border with Egypt, with the Cairo government, Hamas and Israel each having some degree of control over the exit point. Mr Yousaf, the Scottish leader whose family members remain trapped in Gaza after visiting relatives, has released a video on X, formerly Twitter, in which his mother-in-law, Elizabeth El-Nakla, says: “Everybody from Gaza is moving towards where we are. One million people. No food. No water.” There is growing international concern about the potential for a humanitarian disaster in the Gaza Strip after Israel told the 1.1 million civilians in the north of the territory to evacuate before an expected ground offensive. A massive Israeli military operation from air, sea and land is expected after Hamas massacred more than 1,300 Israelis, including babies, in attacks on October 7. More than 2,300 Palestinians have already been killed in retaliatory Israeli air strikes. The Foreign Office said its officials were working with Egyptian authorities to arrange for British and dual citizens to leave Gaza via Rafah. British Prime Minister Rishi Sunak spoke to Egyptian President Abdel Fattah El Sisi about the situation last week. Britain has also readied two Rapid Deployment Teams to support vulnerable citizens seeking places on evacuation flights. It is also working with Israeli air controllers to try to maintain commercial air links and keep a range of transport options under review. While commercial flights remain limited, a small number of routes between Israel and Europe, including the UK, are open. The British government also insisted “vital humanitarian supplies”, including food, water and medical supplies necessary for survival, “must be able to reach innocent civilians”. The Foreign Office has advised against all travel to parts of Israel and the Occupied Palestinian Territories. The Foreign Office has also told British citizens in Gaza to follow Israel’s orders to move out of the northern part of the strip ahead of the likely military assault.