The UN Security Council has criticised Myanmar for slow progress on democratic reforms as its special envoy said the government there was trying to delay his next visit until April.
It said Myanmar's military rulers had done too little to meet its October demand for the release of political prisoners and a genuine dialogue with the opposition.
In a statement, the council called for another visit soon to Myanmar by Ibrahim Gambari, the special UN envoy to Myanmar, who has sought to wring concessions from the government.
The wording was significant in being agreed to by all 15 council members, including China, Indonesia and Vietnam.
Asian countries have been reluctant to take a tough line against Myanmar, a member of the Association of Southeast Asian Nations, which launched a violent crackdown on anti-government protests last September.
Libya's Giadalla Ettalhi, the council president, said: "Council members... regretted the slow rate of progress so far towards meeting those objectives. Council members underscored the importance of making further progress."
Gambari said he was trying to return to Myanmar as soon as possible for his third visit since the crisis erupted but that authorities there were stalling arrangements for the visit.
He said: "I had requested to go there this month. They have sent word that it's not convenient and they will prefer mid-April.
"Now the [UN] secretary-general has said that's not acceptable, and I agree, and so we are in the process of negotiating an early rather than a later return to Myanmar."
Gambari is planning talks in China and India later this month - two countries seen as crucial to any resolution of the Myanmar crisis because of their economic clout and trade ties with the country.
The special envoy said he wanted concrete action and not just verbal support from Myanmar's neighbours.
He said he had noted that a senior governemt official had met detained opposition leader Aung San Suu Kyi last Friday for the fourth time since last September's crackdown, but there was still no sign of real results.
"We don't know what transpired but... these are still processes, and it's important to translate these discussions into the inauguration of a substantive dialogue that will address the grievances of the people, which are both socio-economic as well as political," he said.
Zalmay Khalilzad, the US ambassador to the UN, has said Washington believes it is necessary to increase pressure on Myanmar to get results.
He said that pressure should come from countries with influence on Myanmar, such as China and India, but that the Security Council also should take measures, including sanctions.
Sanctions are thought to have little chance of approval in the council because of opposition from China which hold the power of veto on an any resolutions.