The International Atomic Energy Agency says it is now unlikely to send a delegation to North Korea, after Pyongyang stated it is no longer bound by an agreement with the United States not to test missiles and nuclear devices.

Spokeswoman Gill Tudor made the announcement late Tuesday, ending hopes for the visit for which IAEA officials began negotiating with North Korea in March.

Earlier in the day, Pyongyang said it was breaking off a bilateral agreement to halt its nuclear activities and allow IAEA inspectors to enter the country after the U.S. suspended much needed food aid. Washington said North Korea did not keep its end of the bargain when it carried out its failed missile launch on Friday.

North Korea's Foreign Ministry vowed to continue trying to fire a long-range rocket into space to place what it said was a weather satellite into orbit. It also vowed unspecified retaliation now that the agreement with the U.S. is no longer in place.

State Department spokesperson Mark Toner said Tuesday that Pyongyang's statement was "not surprising, given their recent behavior." He said he could not predict whether North Korea is laying the ground work for a future nuclear test, as some fear.

"Frankly, it's very difficult to say. It's a very opaque regime. We parse out their public comments," said Toner.  "We also know that in the past, there's been this pattern of bad behavior. So we can't preclude anything at this point."

Former CIA Director Michael Hayden also refuses to speculate on whether North Korea could follow up the failed missile launch with such a test. But he tells VOA that he is concerned that the country's new leader, Kim Jong Un, may feel pressured to solidify his power with an additional provocative act.

"We have seen this pattern in the past - where they have a missile launch, the rest of the world has responded, and rather than compromise and negotiate, the North has taken another provocative action. And in two instances, the provocative action has been an attempt at a nuclear test," he said. "So I fear that this is the course of action they may be on."

North Korea on Tuesday also rejected the U.N. Security Council's condemnation of the failed launch. On Monday, the Security Council ordered a tightening of sanctions aimed at preventing North Korea from developing and exporting nuclear and missile technology.  The statement said the council will respond accordingly to any further provocations by Pyongyang.

North Korea insists it was within its legal rights when it launched the rocket last week.  The rocket broke apart and fell into the Yellow Sea.  The launch prompted criticism from the United Nations, long-time North Korean ally China, the United States, Japan, and the European Union.  Critics accused the North of using the satellite scenario as a cover for testing ballistic missile technology banned under United Nations resolutions.