Sana’a: Yemen’s national security chief on Saturday accused Tehran of “damaging Yemen”, as the interior ministry said it was investigating an Iran-linked arms shipment seized last month.

“Such a shipment cannot be made by traders or smugglers... Only an official power stands behind it,” Ali Hassan Al Ahmadi told reporters in Sana’a.

“We have repeatedly urged our brothers in Iran to reassess their stances towards Yemen. They had always denied any interference, but this shipment sadly affirms that they insist on damaging Yemen,” Ahmadi said.

“Yemen will take measures [to] preserve its right to defend its citizens and its sovereignty,” he said.

The coast guard, in coordination with the US navy, on January 23 intercepted in the Arabian Sea a ship carrying rockets and explosives, which authorities in Sana’a say came from Iran. Tehran denies any involvement.

Interior Minister Abdul Qader Qah’tan said in a statement on Saturday that the “arms and explosives shipment seized in Yemen’s territorial waters on January 23 were very dangerous due to the amounts of explosives”.

The ministry said the eight-member crew of the Jihan II were still being interrogated by security services, who are also investigating “other shipments from the same source which entered the country” in May last year.

It said the Jihan II was carrying “40 tonnes of arms, shells and explosives”.

A security official last week said the vessel came from Iran and that the arms “were destined for the Al Houthi rebels in Saada,” the stronghold of Shiite fighters in northern Yemen.

United Nations sanctions experts are investigating the Yemeni government’s claims, New York-based diplomats have said.

In Washington, State Department spokeswoman Victoria Nuland praised the Yemeni government for its “successful and significant interdiction” of the vessel and its decision to alert the UN Security Council.

“These weapons are clearly designed to cause significant damage with the highest possible number of casualties and are a threat to both Yemen and the region,” Nuland said in a statement, urging UN experts to evaluate the arms.

She added that the origin of the ship and weapons “underscores Iran’s ongoing evasion of six relevant UN Security Council resolutions”.

“Iran continues to defy the international community through its proliferation activities and support for destabilising action in the region,” Nuland said.

“The international community must continue to speak with one voice and work to ensure that Iran adheres to all of its international obligations.”

Western nations and Israel have long accused Iran of seeking a nuclear weapon in the guise of a civilian uranium enrichment programme, charges denied by Tehran, which insists its nuclear programme is entirely peaceful.