Kyaw Hsan, the information minister, told Gambari a three-way meeting was premature and he warned that tougher international sanctions would only make matters worse.
"Myanmar will not bow to outside pressure. It will never allow any outside interference to infringe on the sovereignty of the state," state-run MRTV quoted Kyaw Hsan as saying during talks with Gambari in the new capital Naypyidaw.
The United Nations said Gambari "had very frank and extensive exchanges" with senior government officials on the fourth day of a mission aimed at securing talks between Aung San Suu Kyi and the generals who crushed pro-democracy protests in late September.
Gambari urged that dialogue "start without delay as an indispensable part of any process of national reconciliation, and the lifting of restrictions on Daw Aung San Suu Kyi and all political detainees as the necessary steps to that end", the UN office in Yangon said in a statement.
"Until the generals' military hardware is crumbled, they won't listen to anyone"
Oomlwin, Yangon, Myanmar
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But state media said Kyaw Hsan called on Gambari to first press Aung San Suu Kyi to respond to the government's conditions that she end "confrontation" and renounce her support for sanctions against and the "utter devastation" of the country.
Gambari was on Wednesday to meet foreign diplomats whom the government called to the remote capital.
The UN envoy was also due to meet Aung San Suu Kyi in Yangon, Ban said, but there was no word on meeting Than Shwe.
The UN has said Gambari will stay in Myanmar as long as necessary to accomplish his mission, but his work has been complicated by the generals' move to kick out the top UN resident diplomat for highlighting the country's economic crisis.
The government has, however, agreed to a visit by Sergio Paulo Pinheiro, the UN human rights envoy, from November 11 to 15, the first time he has received a visa in four years.