PHNOM PENH, Dec 10 (Reuters) - A senior U.S. official urged Cambodia on Friday not to make any concessions to Myanmar"s military junta when Phnom Peng chairs the Association of Southeast Asian Nations (ASEAN) next year. The remarks by U.S. State Department Counselor Derek Chollet came days after Cambodian Prime Minister Hun Sen said Myanmar officials should be invited to return to ASEAN meetings, following an unprecedented exclusion from this year"s summit. Myanmar has been in crisis since General Min Aung Hlaing overthrew a civilian government led by Nobel laureate Aung San Suu Kyi on Feb. 1, prompting widespread protests and pockets of armed resistance met with violent suppression. The military says its takeover was in line with the constitution and that the opposition are terrorists. Min Aung Hlaing was not invited to ASEAN"s October summit by current chair Brunei over a lack of cooperation with the regional bloc"s peace plan, including not allowing an envoy access to Suu Kyi, who was sentenced on Monday to jail. Chollet, on a brief visit to Phnom Penh, stopped short of calling on Cambodia to continue to exclude Myanmar junta officials, but he urged the country to promote and uphold the ASEAN peace plan. "We would expect of any engagement that it actually brings results, it"s not just something that"s a concession to the junta," he said. "The U.S. is not against engagement - we still have embassy in Myanmar - but we"re quite clear that the engagement needs to have a purpose, you can’t come for free and we want to see genuine progress on the ground.” Myanmar"s military-appointed foreign minister visited Cambodia and met with Hun Sen on Tuesday, a day after the junta drew global condemnation for sentencing Suu Kyi to two years" detention on charges of incitement and breaching COVID-19 rules. Hun Sen, who has faced criticism from rights groups and Western governments over what they see as his suppression of democracy, also pledged to visit Myanmar.