North Korea indicated Tuesday that it might be planning a new ballistic missile test, hours after it said it had no interest in dialogue over its nuclear weapons.
In a rare news conference at its U.N. mission in New York, Ambassador Jang Il Hun told reporters, "We stated in the past that we will respond to the military deterrence and pressure of the United States with modernization and expansion of our nuclear forces."
Jang said Pyongyang would not rule out the possibility of "doing one of these things."
South Korea's Yonhap news agency reported last week that the North had built a new rocket launch tower, bigger than the one used to fire a suspected ballistic missile in 2012. Analysts have speculated that Pyongyang may try a launch in October to mark the ruling party's 70th anniversary.
U.N. resolutions bar Pyongyang from any ballistic missile activity, and previous test launches have led to sanctions against the reclusive communist state.
But Jang said Tuesday that North Korea was "free to do whatever we want."
Earlier Tuesday, North Korea's ambassador to China, Ji Jae Ryong, said the North had no interest "in dialogue for unilaterally freezing or giving up our nukes."
Ji called Pyongyang's situation "totally different" from that of Iran, which just signed a nuclear deal with six world powers. The pact will limit Iran's nuclear capabilities in exchange for sanctions relief.
"We are a nuclear state, both in name and reality," Ji said during a rare news conference at the North Korean Embassy in Beijing. "As a nuclear state, we have our own interests in a nuclear program."
He said North Korea needed its nuclear weapons to "restrain the provocative nuclear war acts of the U.S."
The comments came as senior U.S. envoy Sydney Seiler visited Beijing on Tuesday for talks on how to revive the stalled six-party nuclear talks with North Korea.
After meeting with officials in Seoul on Monday, Seiler said the U.S. was ready to engage Pyongyang in the same way it helped broker a deal with Iran.
"The recent progress in our efforts at denuclearization with Iran provides an excellent example of the U.S. flexibility and willingness to engage with countries with whom we've had long-standing differences," he said.
North Korea has conducted three nuclear tests. Its most recent test in 2013 prompted the U.N. Security Council, led by China and the United States, to pass severe sanctions on North Korean banking, travel and trade.
North Korea in 2009 walked out of six-nation talks aimed at persuading it to give up its nuclear program in exchange for badly needed aid and security guarantees. Those talks included the two Koreas, the U.S., China, Japan and Russia.