PYONGYANG (Reuters) - Syria’s ambassador to North Korea denounced what he called U.S. aggression and its “history of interventions” on Monday and said that it sending a “message” to North Korea with an attack on a Syrian airfield was irresponsible.

A combination image released by the U.S. Department of Defense which they say shows the impact crater associated with April 4, 2017 Chemical Weapons Allegation released after U.S. cruise missile strike against Syria on April 7, 2017. Courtesy U.S. DoD/Handout via REUTERS

North Korea has conducted several missile and nuclear tests in defiance of U.N. sanctions and has said it has developed a missile that can strike the U.S. mainland. Its latest missile test on Sunday failed a few seconds after launch.

U.S. Vice President Mike Pence warned North Korea on Monday that recent U.S. strikes in Syria, one of North Korea’s few close allies, and Afghanistan showed that the resolve of President Donald Trump should not be tested.

The U.S. Navy this month struck a Syrian airfield with 59 Tomahawk missiles after a chemical weapons attack. On Thursday, the U.S. military said it had dropped the largest non-nuclear device it had unleashed in combat on a network of caves and tunnels used by Islamic State in Afghanistan.

Syrian Ambassador to North Korea Tammam Sulaiman said the United States was wrong to send messages with attacks on other countries.

“Whatever they do, this is clear aggression. If they want to mention this they ought to do this as a message or whatever, it has no sense to talk about this,” he told Reuters, in English.

“Because what is sense is to see whether the U.S. is really serious in finding solutions, whether in Syria or Korea. If they want to keep sending messages, then you are not talking with a responsible state or a responsible administration. It is not about giving messages, it is about taking a position.”

A high-level government official at North Korea’s Ministry of Foreign Affairs told Reuters in a separate interview on Monday that North Korea would have been attacked a long time ago like other countries if it did not have strong military capabilities.

“The Syrian incident proves that our policy to bolster our national defence capabilities by tightening our belts is the correct policy,” said Kim Son Gyong, Director General of the European Department at North Korea’s Ministry of Foreign Affairs.

Asked whether he thought the U.S. was sending Pyongyang a message by striking Syria, he said: “We are not startled or surprised in the slightest by this kind of act. If the U.S. thinks this kind of thing will startle us, then they have misjudged us.”

North Korea’s KCNA news agency on Monday carried a letter from leader Kim Jong Un to Syrian President Bashar al-Assad marking the 70th anniversary of Syria’s independence.

“I express again a strong support and alliance to the Syrian government and its people for its work of justice, condemning the United States’ recent violent invasive act against your country,” Kim said.

Asked to what extent North Korea supported the Syrian military in its fight against rebel forces, Sulaiman said there was “nothing of military cooperation”.

North Korea in 2013 denied it was sending military aid to the Syrian government after media reports said that Pyongyang had sent advisers and helicopter pilots.

Kim Son Gyong declined to comment when asked about the kind of military aid North Korea currently provides Syria.

Sulaiman said the “acquisition of nuclear weapons should not be a goal” for any country.

“But I can understand in the case of North Korea, I can understand why (it) is building its nuclear capabilities to face the American aggression, clear aggression.”