UNITED NATIONS (Reuters) - The U.N. Security Council plans to vote later on Tuesday on a draft resolution that condemns North Korea for its December rocket launch and calls for tightening existing U.N. sanctions, council diplomats said.

The U.N. media office confirmed that the 15-nation council would discuss North Korea at a meeting on unrelated issues that begins at 3:00 p.m. EST (2000 GMT) on Tuesday. U.N. diplomats said on condition of anonymity that they were planning to vote on the U.S. drafted resolution.

The draft was the result of a deal between the United States and China, envoys said. Even though it does not call for any new sanctions against Pyongyang, diplomats said China's support for the resolution represented a significant diplomatic blow to Pyongyang.

The draft, which was sent to the 15 council members, calls for sanctioning a number of additional North Korean entities, including Pyongyang's space agency, diplomats said on condition of anonymity.

It also adds the head of the North Korean space agency and several other individuals linked to firms involved in the nation's nuclear and missile industries to the U.N. blacklist, they said.

North and South Korea are still technically at war because their 1950-53 conflict ended in a truce, not a treaty.

The United States had wanted to punish North Korea for the rocket launch with a Security Council resolution that imposed new sanctions against Pyongyang, but Beijing rejected that option.

China is the North's only major diplomatic ally, although it agreed to U.N. sanctions against Pyongyang after North Korea's 2006 and 2009 nuclear tests.

North Korea is already banned under Security Council resolutions from developing nuclear and missile technology. But it has been working steadily on its nuclear test site, possibly in preparation for a third nuclear test, satellite images show.

December's successful long-range rocket launch, the first to put a satellite in orbit, was a coup for North Korea's young leader, Kim Jong-un.

(Reporting By Louis Charbonneau; Editing by Mohammad Zargham and Philip Barbara)