Iran’s ambassador to the United Kingdom has again denied any Iranian involvement in an alleged “terrorism” plot at RAF Fairford airbase last month.

Ali Mousavi told British authorities that Tehran was ready to cooperate with the investigation into the incident at the airbase, in which five men were arrested and later released on bail, The Caspian Post reports, citing Al Jazeera.

During a meeting with Stephen Doughty, Britain’s minister for the Middle East, Mousavi “categorically rejected” allegations of Iranian involvement and urged the British side to refrain from making “any unsubstantiated statements.”

Iran’s embassy had also denied any involvement in the incident last month, describing the accusations as “Iranophobia propaganda.”