A top Iranian official said Sunday that Iran would not back a peace plan in Syria that included removing President Bashar Assad, the Associated Press reported. Iran has long been a staunch ally of Syria and has sent forces to the country to bolster its military. 

"Iran believes that the government of Bashar al-Assad should remain in power until the end of the presidency term," top Iranian adviser Ali Akbar Velayati said on state-run television.

News of Valayati’s statement came as fighting between rebel forces and the government military continued in the Western city of Hama, Syria, with clashes between the al Qaeda-affiliate Nusra Front and Assad’s forces.

Iran has backed Assad throughout the five-year conflict by sending both military and advising support staff to Syria. The Syrian conflict began in 2011 with anti-government protests that turned violent after security forces fired on protesters, and they eventually spiraled into all-out war. Anti- and pro-government sides have increasingly fractured in the five years since along sectarian lines, allowing for terror groups such as the Islamic State group – also known as ISIS – to capture vast swaths of Iraq and Syria.

The U.S. has led the coalition conducting airstrikes against ISIS while working with its allies on the United Nations Security Council to secure a peaceful end to the conflict. President Barack Obama has insisted that Assad's removal would be a key part to any successful plan for peace in Syria. “The reason is not simply because of my opinion of him. It is because it is unimaginable that you can stop the civil war here when the overwhelming majority of people in Syria consider him to be a brutal, murderous dictator,” Obama said in November.

A partial ceasefire that began in February and was brokered in part by Washington, and Moscow made no mention of Assad’s removal, however, as this question has long been a point of contention with both Russia and Iran.