KUWAIT CITY — Kuwait said Thursday that it is shutting the Iranian cultural mission and calling for a reduction in the number of Iranian diplomats stationed in the country, deepening a rift between the Gulf Arab states and Tehran.

The official Kuwait News Agency announced the move in a brief statement, linking the decision to the case of a terror cell broken up in 2015 that authorities allege had contacts with Iran and the Lebanese Shi’ite militant group Hezbollah.

The Iranian ambassador to Kuwait has been notified of the decision, the news agency, known as KUNA, reported.

Embassy staff did not respond to requests for comment.

Iran’s state-run IRNA news agency reported that the country’s foreign ministry summoned the Kuwaiti chargé d’affaires in Tehran to explain the move.

The ministry is protesting the call to cut the number of diplomats stationed in Kuwait, IRNA said.

Later, the ministry’s website, mfa.ir, reported that the spokesman, Bahram Ghasemi, rejected all accusations against Iran and said that Tehran will take counter-action.

The 2015 case centers on a group of 26 people known as the Al Abdali cell whose arrests for links to Shi’ite powerhouse Iran touched on sensitive sectarian issues in Kuwait, a Sunni-majority country.

Besides having ‘‘furtive contacts’’ with Hezbollah and Iran, its members were accused of weapons possession and of planning ‘‘hostile actions’’ inside Kuwait, a tiny US-allied Arab state.

associated press