TEHRAN (Reuters) - Iran on Sunday confirmed its adherence to Iran's missile system and vowed to continue its "test and development", saying it would strengthen its "defensive and deterrent" capabilities and could not be negotiated.

Iranian Armed Forces spokesman Brigadier-General Abu al-Fadl Shakarji confirmed that his country would continue to test and develop its missile systems.

In response to remarks by US Secretary of State Mike Pompeo on Iran's testing of a ballistic missile, Shakarji said: "The missile program is linked to Iran's national security and can not be negotiated, and Iran will not allow anyone to interfere with its missile program."

Shakarji said that his country's missile tests "do not target any of the countries in the region and that they are only aimed at strengthening Iran's defense capabilities," but he did not confirm or deny that his country had tested a new missile.

Iranian Foreign Ministry spokesman Bahram Qasimi said Iran's missile program was "defensive and tailored to Iran's needs and did not violate UN resolutions."

"There is no Security Council resolution that bars Iran's missile program or missile tests. It is funny that the US secretary was based on an international resolution that was vetoed by the United States before its unilateral withdrawal from the nuclear deal," he said.

US Secretary of State Mike Pompeo said on Saturday that Iran had tested a medium-range ballistic missile with multiple warheads, saying that the test violated UN Security Council Resolution 2231.

"Iran's expansion in testing and deployment of missiles is growing steadily, and America condemns this action and calls on Iran to stop these activities," he said in a tweet.