Syrian President Bashar al-Assad hailed the "resilience" of Iran in striking a landmark nuclear deal with world powers, according to his Facebook page on Wednesday.
"In a telephone call to President Hassan Rouhani of the Islamic Republic of Iran, President Assad reaffirmed the Iranian diplomatic success... leading to the deal with the P5+1 countries."
The posting on Assad's page said the deal was "the result of the Iranian people's resilience, who held onto their rights, and of the Iranian leadership's commitment to the principles of Iran's sovereignty."
The agreement reached on Sunday in Geneva rolls back part of Iran's nuclear work and freezes further advances in exchange for limited relief from sanctions which have choked Iran's economy.
Western nations and Israel have long accused Iran of seeking a nuclear weapons capability alongside its civilian programme, charges denied by Tehran, which insists its uranium enrichment is purely for energy and medical research.
The deal followed a decade of deadlock and was finally struck between Iran and the so-called P5+1 group of the United States, Britain, France, China and Russia plus Germany.
Along with Russia and China, Iran is a key supporter of Assad, while the United States, Britain and France back the opposition and have led international calls for the embattled Syrian leader to step down.