The U.N. Office for the Coordination of Humanitarian Affairs said more than 4,000 people in Kachin received food, medicine and other supplies. The delivery this week was the first since December 2011.
OCHA spokesman Jens Laerke said from Geneva there may be another 53,000 people in need of assistance.
"The United Nations and our partners in Myanmar are telling us that it is essential that this convoy should be the first of many to the area to help the people there," he said Tuesday.
The government in January announced a unilateral cease-fire with Kachin rebels fighting for more autonomy. The truce followed a three-week military campaign and both sides have since agreed to work toward a long-term settlement.
Myanmar said it was planning a comprehensive peace initiative next month aimed at resolving disputes with armed groups in the country. A delegation representing the movements said they were pessimistic about the outcome.
Myanmar received international praise for political reforms that started with general elections in 2010. It's been criticized, however, for its national security and human rights record.
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