North Korea transported an object believed to be the main portion of a long-range ballistic missile to a missile launch facility in the country's northwest, RIA Novosti reported citing Kyodo news agency.

The information is based on images obtained from surveillance satellites, the agency said.

It is likely to be the ''carrier rocket'' for the launch of an observation satellite that North Korea plans to carry out in mid-April to mark the 100th anniversary of its late founding leader Kim Il-sung.

The international community, including Russia and the United States, has condemned the launch, which they suspect is a thinly veiled ballistic missile test. The Japanese Armed Forces warned they could shoot down the rocket.

Pyongyang accused its critics of attempting to encroach on its sovereignty and said it had no intention of cancelling the plans.

UN Security Council Resolution 1874 prohibits North Korea from conducting launches that use ballistic missile technology. A similar launch in 2009 drew international criticism and led to UN Security Council sanctions.

The launch comes a day before an international nuclear security summit opens in South Korea’s Seoul to be attended by more than 53 world leaders and international organizations.