King Charles spoke with President Isaac Herzog on Wednesday, expressed his deepest condolences to the citizens of Israel and and deep shock at Hamas's attack on Saturday.
Herzog thanked the king for his support and the two talked at length about the massacre conducted by Hamas.
Britain's King Charles is appalled by the "barbaric acts of terrorism" in Israel, a Buckingham Palace spokesperson said on Wednesday, following attacks by the Palestinian militant group Hamas.
"This is a situation His Majesty is extremely concerned about, and he has asked to be kept actively updated," the spokesperson said. "His thoughts and prayers are with all of those suffering, particularly those who have lost loved ones, but also those actively involved as we speak."
Israel's death toll has reached 1,200 with more than 2,700 wounded, its military has said, during the Hamas militants' hours-long rampage after breaching the border fence around Gaza on Saturday.
"His majesty is appalled by and condemns the barbaric acts of terrorism in Israel," the palace spokesperson said.
Charles' long standing relationship with Israel
Charles became the most senior British royal to pay an official visit to Israel and the Palestinian Territories in 2020 when he met former Israeli President Reuven Rivlin and Palestinian President Mahmoud Abbas.
During his trip he spoke of the evil of the Holocaust and the dangers of antisemitism, as well as expressing sadness over the suffering and hardship faced by Palestinians.
Charles, who had previously traveled to Jerusalem in 1995 and 2016 to attend the funerals of Prime Minister Yitzhak Rabin and President Shimon Peres, also visited the tomb of his grandmother, Princess Alice of Greece, who is buried on Jerusalem’s Mount of Olives.
She was honored by Israel for sheltering Jews in her palace in Nazi-occupied Greece during the Holocaust.