Nay Pyi Taw, Sep 28: A planned visit by UN officials to Myanmar's Rakhine state, which has seen a mass exodus of Rohingya Muslims, has been postponed by the country's authorities, the world body said on Thursday. The government-organised trip will now happen next week, a UN spokesman said. The visit would have been the first by UN officials to the area since violence broke out on August 25, the BBC reported. A UN spokesman in Yangon initially told the BBC no reason was given for the postponement, but later said it was due to bad weather. UN aid personnel were forced to leave Rakhine when the military began a crackdown on Rohingya militants for attacks on security personnel. The UN had been pushing to visit Rakhine to investigate the flight of 480,000 Rohingya Muslims to Bangladesh in a month. Rohingyas, who had crossed the border, accused Myanmar's military, backed by Buddhist mobs, of trying to drive them out with a brutal campaign of beatings, killings and village burnings. But the military said it was only targeting militants. Earlier this week, it said bodies of 45 Hindus killed by Rohingya militants had been found in a mass grave. According to several humanitarian groups, in addition to those who have fled to Bangladesh, many people were displaced within Rakhine and hundreds of thousands lack food, shelter and medical care. On Wednesday, UN refugee chief Filippo Grandi called on the Myanmar authorities to halt the violence as he said that Rohingya refugees who fled violence in Myanmar were in desperate need of help. "They have absolutely nothing... Evidently they had to flee from a very urgent situation, from very sudden violence -- so they need everything." Grandi said that including some 300,000 Rohingya refugees already in Bangladesh, between 700,000 and 800,000 people were now sheltering there in overcrowded and insanitary conditions, posing a risk of epidemics.