A draft resolution calling for tougher sanctions against North Korea's December rocket launch is being circulated among members of the U.N. Security Council, who are poised to pass it as early as Wednesday, a Seoul diplomatic source said Monday.

"To my knowledge, the draft resolution will be put to a vote early this week and adopted on Wednesday or Thursday (Seoul time), unless there is another variable," said the source with direct knowledge of the U.N. debate.

The Security Council is set to convene a meeting to vote for the resolution, the source said on the condition of anonymity.

The draft resolution comes after China reversed its stance against taking strict actions against the North and agreed to punish Pyongyang with a U.N. resolution for its defiant rocket launch.

South Korea and the U.S. have been pushing to get the Security Council to adopt stiffer sanctions against North Korea in response to its Dec. 12 rocket launch, but China had apparently wanted the council to issue a statement, or a symbolic condemnation against the North's launch.

A diplomatic compromise came last week after the U.S. and China reached a tentative deal on the draft resolution that will tighten existing sanctions against North Korea, rather than imposing new ones, according to the source.

Details of the new U.N. resolution are unknown, but, if adopted, it will add more North Korean individuals and entities to the list of sanctions already in place for its earlier nuclear tests, the source said.

Asked whether the new resolution would include a reference of Chapter 7 of the U.N. Charter, the source replied, "It remains to be seen."

The Chapter 7 allows the Security Council to use its authority to impose a range of measures including breaking diplomatic ties, imposing economic and military action, according to Seoul diplomats.

North Korea has been under U.N. sanctions since 2006 when it conducted its first nuclear test. The sanctions were tightened in 2009 after its second nuclear test.

Concerns persist that North Korea may conduct a third nuclear test following the latest rocket launch as it did with the previous two rocket launches.

South Korea's defense ministry, along with U.S. scientists, has scrutinized the debris of the North Korean rocket launched last month since recovering the remnants of its oxidizer tank and parts of its engine.

After 29 days of scrutiny, in what was the first detailed analysis of North Korea's rocket technology using the rocket's real components, the ministry said Monday that the North has made a technical advance to build a homegrown intercontinental ballistic missile that could fly more than 10,000 kilometers.

The estimated range puts the West Coast of the U.S. in range, although North Korea has not been believed to develop the re-entry technology designed to deliver a missile.

"Most of core components used in the long-range missile were manufactured by North Korea itself," a senior official at the ministry's Defense Intelligence Agency told reporters.

Other non-core parts such as a temperature detector, direct-current conversion equipment and a pressure sensor used in the North's rocket were found to be produced in China and some European nations. The parts do not appear to be in violation of the Missile Technology Control Regime (MTCR), according to the intelligence official.

The South Korean government plans to inform the U.N. and MTCR members of the analysis results regarding the North Korean rocket, ministry officials said.

The North's December rocket launch demonstrated its ability to put a satellite into orbit, but the satellite is not functioning, the intelligence official said.

"It appeared to be positioned in geostationary orbit, but no transmissions take place," the official said. (Yonhap News)