White House says Tehran is providing Yemeni rebel group with weapons and tactical intelligence.

Tehran’s support for the Yemeni rebel group includes both weapons and tactical intelligence, the White House said on Friday as it presented newly declassified intelligence purporting to show Iranian involvement in the attacks.

“We know that Iran was deeply involved in planning the operations against commercial vessels in the Red Sea,” White House national security spokeswoman Adrienne Watson said in a statement.

“This is consistent with Iran’s long-term material support and encouragement of the Houthis’ destabilising actions in the region.”

“This is an international challenge that demands collective action,” Watson said.

The White House said that visual analysis showed nearly identical features between Iran’s KAS-04 drones and the unmanned vehicles used by the Houthis, as well as consistent features between Iranian and Houthi missiles.

Al Jazeera could not independently verify the White House’s claims.

The Houthis, who control large parts of Yemen including the capital Sanaa, have launched dozens of drone and missile attacks on commercial shipping in the Red Sea in what the group has described as a show of support for Palestinians facing Israeli bombardment in Gaza.

The attacks have effectively rerouted a large portion of global trade by forcing freight companies to sail around Africa, imposing higher costs and delays to deliveries of energy, food and consumer goods.

More than a dozen shipping companies, including the Italian-Swiss giant Mediterranean Shipping Company, France’s CMA CGM and Denmark’s AP Moller-Maersk, have suspended transit through the Red Sea due to the attacks.

Washington earlier this week announced the launch of a multinational force, involving more than 20 countries, to protect vessels transiting the Red Sea.

Last week, a US guided-missile destroyer shot down 14 attack drones believed to have been fired from Houthi-controlled regions of Yemen.

The Houthi leadership has warned that they will strike back at “American battleships” and “American interests” if they are attacked.

Tehran has said it supports the Houthis politically but denies sending the group weapons.

Iran’s Ministry of Foreign Affairs last month rejected Israeli accusations that the Houthis were acting with its guidance when they seized an Israeli-owned ship and denied responsibility for a drone shot down by a US guided-missile destroyer.

The Houthis, which have effectively maintained a United Nations-brokered truce with the Saudi-backed government since last year, rose up against the Yemeni government in 2014, triggering a devastating civil war.