A top Iranian military official dismissed President Donald Trump’s claim that Iran was behind a ballistic missile attack on Riyadh on Saturday, describing it as slander.

Saudi air defenses intercepted the missile before it could strike its intended target, destroying the missile above Riyadh’s international airport and causing little to no damage. Yemen’s Houthi-controlled government claimed responsibility for the attack, as it has for dozens of other similar attacks over the course of the war between Houthi rebels and a Saudi-led coalition that has been raging since March 2015.

But Houthi rebels in Yemen have not shown the technical capability to construct a ballistic missile capable of reaching Riyadh on their own, leading Saudi and U.S. military officials to renew focus on their claim that Iran, and specifically the covert action wing of the government, the Iranian Revolutionary Guard Corps (IRGC), is escalating their proxy war in Yemen.

Yemen did possess numerous short ranged ballistic missiles on their own prior to the start of hostilities with Saudi Arabia over two years ago, acquired through arms deals with North Korea and the former Soviet Union. The ballistic missiles that Yemen’s defense ministry maintained throughout the turbulent power transfers between Ali Abdullah Saleh and current President Abdrabuh Mansur Hadi have been used extensively in the current war, although their effects within Saudi Arabia have been limited due to an effective Saudi Patriot Missile defense system.

Houthi forces said the missile fired on Saturday was a Burqan-2H, a type of missile unveiled by the rebels earlier this year that is reportedly a modified and improved version of the Burqan, which has a range of 800 kilometers and was used last year in attacks on two Saudi air bases.

“A shot was just taken by Iran, in my opinion, at Saudi Arabia … and our system knocked the missile out of the air,” President Trump told reporters this weekend.

An Iranian IRGC leader, Mohammad Ali Jafari, responded by saying “Mr Trump has said many baseless things and told many lies and frequently falsely accused Iran and this one of those slanders.”

“We do not have even the possibility to transfer missiles to Yemen,” Jafari said, referring to the sanctions and blockade imposed by the United States and other countries which ostensibly prevents weapons shipments from Iran. “The missiles belong to them and they have increased their range.”