The six-state Gulf Cooperation Council (GCC) designated Wednesday Lebanon’s Shia Hezbollah a "terrorist organization".
The council took the move against Hezbollah "because of hostile actions by the militia, which recruits young people for terrorist acts," GCC Secretary-General Abdullatif al-Zayani said in a statement.
He said the GCC countries -- Saudi Arabia, Kuwait, the United Arab Emirates, Qatar, Bahrain and Oman -- see Hezbollah’s actions in Syria, Yemen and Iraq as "a threat to Arab national security".
"As the militia continues its terrorist practices, the GCC states have decided to designate it a terrorist organization and will take the necessary measures to implement its decision in this regard based on anti-terrorism laws applied in the GCC and corresponding international laws," the statement read.
In 2013, the GCC imposed sanctions on Hezbollah members in response to the group’s involvement in Syria’s ongoing civil war, in which it supports the Assad regime.
Last month, Saudi Arabia cancelled a promised $3-billion grant to the Lebanese army for the purchase of French arms and a $1-billion grant to the country’s internal security forces -- a move backed by the GCC.
Following the move, the GCC -- in a veiled reference to Shia Iran -- voiced its "deep regret" that Lebanese policy had become "hostage to the interests of external regional powers".
Saudi Arabia and some other Gulf States have gone so far as to warn their citizens against traveling to Lebanon, calling on their nationals living in the country to leave.
Saudi Arabia accuses Shia Hezbollah -- Lebanon’s most powerful military force -- of serving as a proxy for Iran and of hijacking Lebanese policy-making.
Hezbollah, for its part, denounces Saudi military intervention in Yemen, where Riyadh is leading a fierce campaign against the Shia Houthi militant group, which in 2014 overran much of the country and which Saudi Arabia accuses of serving Iranian interests.