North Korea threatened Wednesday to conduct a nuclear attack against the U.S. unless the latter changed its hostile policy, according to Rodong Sinmun, a mouthpiece for the ruling Workers’ Party. The warning, cited by South Korea's Yonhap News Agency, came a day after the party announced that its seventh congress will be held on May 6 in the capital Pyongyang, making it the first in the country since 1980.

“Our patient proposals were completely denied by the United Sates,” Rodong Sinmum said in the commentary. “If the U.S. dares provoke the DPRK [Democratic People's Republic of Korea] in disregard of the reality, it will only meet the catastrophic disaster in which its land may be reduced to debris by the latter's nuclear strike of justice.”

“What is clear is that if the U.S. persistently pursues its hostile policy toward the DPRK, the latter is compelled to take the counter measures for self-defense and the U.S. mainland is bound to be exposed to a nuclear disaster and the day of its ruin on our planet is also bound to come earlier,” it added.

The announcement of the date for the next congress was made amid speculations that Pyongyang may conduct its fifth nuclear bomb test in order to strengthen the military credentials of its leader, Kim Jong Un. The reports come even as the reclusive nation continues to face international sanctions from the United Nations Security Council. North Korea’s official Korean Central News Agency (KCNA) did not clarify how long the congress will last and what would be discussed or determined during the meeting, the Associated Press (AP) reported. The last convention, which took place over three decades back, continued for five days.

The AP report also cited a previous KCNA report that said the Kim Jong Un regime had decided to hold the convention because North Korea was faced with “the heavy yet sacred task” of building a “thriving” country. South Korean analysts told the AP that Kim plans to use the convention to reshuffle senior officials, disclose policy directions and to embolden his power in the country.

On Tuesday, Yonhap reported that Pyongyang appeared to be getting ready to test-launch an intermediate-range ballistic missile after a failed test of a Musudan earlier this month. Musudan, a missile with a range of over 1,800 miles, has the capability to reach as far as Japan and the U.S. territory Guam.

Reports have speculated that the country's next nuclear test could take place even before the congress in May. After its last nuclear test in January, sanctions were slapped against North Korea by the U.N. Security Council while the U.S. discussed the deployment of the Terminal High Altitude Area Defense missile system (THAAD) with South Korea.

Seoul and Washington also have been conducting their annual military drills, a move that has been dubbed as provocation by Pyongyang. On Tuesday, U.S. State Department spokesman Mark Toner said that if North Korea conducts another nuclear test, the U.S. would consider “other” options.

“I think it's pretty clear that as North Korea continues to make decisions that we believe are counterproductive, that we've got to also continually look at what our options are in terms of response. ... We don't want to announce anything before it's been fully formed and fully vetted,” Toner said during a daily briefing.

Since its nuclear tests and a rocket launch in February, North Korea has conducted several missile tests, including what it claims to be a submarine-launched ballistic missile on Saturday.