Myanmar's military government came under pressure on Wednesday to open its borders to more international help after a devastating cyclone that a US diplomat said may have killed more than 100,000 people. The United States said humanitarian access should not be a political matter. “What remains is for the Burmese government to allow the international community to help its people. It should be a simple matter. It is not a matter of politics,” US Secretary of State Condoleezza Rice told reporters in Washington. UN Secretary-General Ban Ki-moon urged Myanmar do more to facilitate international aid. Even relief workers of the United Nations, which has a presence in the diplomatically isolated Southeast Asian country, were awaiting visas five days after the cyclone struck with 190 kph (120 mph) winds. John Holmes, UN undersecretary-general for humanitarian affairs, said four Asian UN officials who do not need visas because of their nationality had been cleared to go as part of an initial assessment team but as many as 100 UN staff from various agencies were still waiting. He said they had not been refused visas, but the process was taking too long. Holmes urged Myanmar to waive visa requirements and customs clearance for aid supplies, noting that similar waivers were granted by Pakistan and Iran after earthquakes there. Limited international aid has trickled in and the military junta's own aid operation has moved up a gear with some helicopter drops into the region, but land convoys were nowhere to be seen, a witness in said. At Yangon airport, a Reuters photographer on a Thai military plane said two Indian and one Chinese transport plane with tents and construction materials had also landed. State Myanmar radio and television, the main official sources for casualties, reported a death toll of 22,980 with 42,119 missing and 1,383 injured in Asia's most devastating cyclone since a 1991 storm in Bangladesh killed 143,000. The UN humanitarian official said the death toll could rise “very significantly.” A US diplomat was more specific. “The information that we're receiving indicates that there may well be over 100,000 deaths in the delta area,” Shari Villarosa, the charge d'affaires of the US embassy in Myanmar, told reporters on a conference call from Yangon. She said the 100,000 figure was not a confirmed death toll but was based on estimates by an international non-governmental organization, which she declined to identify.