The United States and Russia have reportedly agreed in principle that Iranian forces should withdraw from Syria, which Israel and America have long advocated, but Russia believes that it will be a “difficult task” to get Iran out of the country, according to a senior U.S. official, as reported by Haaretz.

This development comes ahead of an upcoming visit to Geneva by U.S. National Security Adviser John Bolton, who will meet with senior Russian officials, focusing on issues related to Iran and Syria.

So far, Russia—an ally of Iran and Syrian President Bashar Assad—has promised Israel to keep Iranian forces almost 53 miles away from the Israeli-Syrian border, a plan that Israeli Prime Minister Benjamin Netanyahu has rejected.

Bolton’s upcoming meeting is considered a follow-up to last month’s meeting between U.S. President Donald Trump and Russian President Vladimir Putin, when the former said that the latter “is helping Israel.”

“This will bring peace to Golan Heights, and bring more peaceful relationship between Syria and Israel, and also to provide security of the state of Israel,” said Putin, speaking through a translator, in Helsinki.

“President [Trump] paid special attention to the issue during today’s negotiations,” added Putin. “And I would like to confirm that Russia is interested in this development and will act accordingly.”

Iranian President Hassan Rouhani thanked Putin in Kazakhstan last week for the effort between the two nations to strengthen Syria’s government.