SEOUL--The powerful sister of North Korean leader Kim Jong Un on Thursday dismissed U.S. calls for a return to diplomacy and lambasted its condemnations of the North’s recent spy satellite launch, vowing more launches in violation of U.N. bans.

During a U.N. Security Council meeting earlier this week, the U.S. ambassador to the United Nations, Linda Thomas-Greenfield, called the North’s satellite launch a “reckless, unlawful” action that threatens its neighbors. But she reiterated the U.S. offer for dialogue without any preconditions, saying North Korea “can choose the timing and topic.”

Kim’s sister and senior official, Kim Yo Jong, rejected the U.S. overture and threatened more satellite and other weapons launches.

“The sovereignty of an independent state can never be an agenda item for negotiations, and therefore, (North Korea) will never sit face to face with the U.S. for that purpose,” Kim Yo Jong said in a statement carried by state media.

“(North Korea) will continue to make efforts to develop everything belonging to its sovereign rights and continue to exercise the sovereign rights, enjoyed by all the member states of the U.N., in a dignified manner without being restricted in the future, too,” she said.

Multiple U.N. Security Council resolutions ban North Korea from performing any launches using ballistic technology, such as satellite liftoffs and missile tests. But the North has argued it has sovereign rights to launch spy satellites and test-flight ballistic missiles to cope with what it calls U.S.-led military threats. It views major U.S.-South Korean military drills as invasion rehearsal and often reacts with its own weapons tests.

Kim Yo Jong said the U.N. Security Council meeting last Monday was convened at “the gangster-like demand of the U.S. and its followers.” She said Thomas-Greenfield must first explain why U.S. strategic assets have frequently appeared at South Korean ports, rather than branding the North’s satellite launch as “illegal.”

She apparently referred to the increasing temporary deployments of powerful U.S. military assets like aircraft carriers and nuclear-powered submarines in line with an earlier U.S.-South Korean agreement to boost their defense against North Korea’s evolving nuclear threats.

In 2018, Kim Jong Un and then U.S. President Donald Trump launched high-stakes diplomacy on the future of the North’s advancing nuclear arsenal. But their summit diplomacy fell apart a year later in 2019 due to wrangling over international economic sanctions on North Korea. Kim Jong Un has since focused on expanding and modernizing his nuclear arsenal, a move experts say he thinks would give him greater leverage to win U.S. concessions in future negotiations.

Spy satellites are among many high-tech weapons systems that Kim Jong Un has publicly pledged to introduce. He said North Korea needs several spy satellites to better monitor its’ rivals’ moves and bolster the precision-guided missile strike capability against enemy targets.

After two failed launch attempts earlier this year, North Korea claimed to put its first military reconnaissance satellite into orbit last week. The North has since claimed its “Malligyong-1” spy satellite was transmitting imagery with space views of key sites in the U.S. and South Korea, such as the White House and the Pentagon. North Korea has not released any of those satellite photos.

U.S. and South Korean officials confirmed the North Korean satellite entered orbit. Outside experts still doubt whether the North Korean satellite can produce militarily meaningful high-resolution imagery.

“I will say that there are plenty of images of the Pentagon and the White House online, so I’ll just leave it at that. Yeah?” Pentagon press secretary Brig. Gen. Pat Ryder told a briefing Tuesday.

South Korean officials said Russian support likely enabled North Korea to put a spy satellite into orbit amid a growing cooperation between the two countries. After retrieving debris from the North’s first failed satellite launch in May, South Korea’s military said the North’s spy satellite wasn’t advanced enough to conduct reconnaissance duties. But South Korean Defense Minister Shin Wonsik said last Friday that he worries Russia could help North Korea produce higher-resolution satellite photos.

North Korea’s two failed satellite launches and barrage of banned ballistic missile tests since last year didn’t earn the country fresh U.N. sanctions because Russia and China, both permanent members of the U.N. Security Council, have stymied any Security Council response amid separate confrontations with the U.S.

The spy satellite launch deepened animosities between North and South Korea, with the rivals taking respective hostile military steps along their heavily fortified border in breach of their previous tension-reduction deal.