President Donald Trump has said it was time the United States "fully" recognises Israel's sovereignty over the disputed Golan Heights, which it captured from Syria in 1967.
The Golan Heights is of "critical strategic and security importance to the State of Israel and regional stability," Trump tweeted on March 21.
There was no immediate response from the Damascus government, which has which has sought to regain control of the plateau.
Israeli Prime Minister Benjamin Netanyahu tweeted his thanks to Trump.
"At a time when Iran seeks to use Syria as a platform to destroy Israel, President Trump boldly recognises Israeli sovereignty over the Golan Heights," wrote Netanyahu, who has claimed that Iran was using the region as a staging area for attacks targeting Israel.
Israel captured the 1,800-square-kilometer Golan Heights from Syria during the 1967 Six-Day War.
In 1981, Israel extended its laws to the region, effectively annexing it, in a move that has not been recognized by the international community.
Israel also captured East Jerusalem during the 1967 war and has declared the entire city its capital. Palestinians claim East Jerusalem as the capital for their proposed independent state.
In 2017, Trump recognized Jerusalem as Israel's capital and ordered the U.S. Embassy to relocate there from Tel Aviv.
Trump's statement came as Secretary of State Mike Pompeo was in Israel and less than a month ahead of Israel's April 9 general elections in which Netanyahu is facing a stiff challenge from a centrist alliance.
The Israeli prime minister is set to visit Washington next week and meet with Trump.