The foreign ministers of Malaysia and the Philippines also called for the release of Suu Kyi.
But some countries were less emphatic and a statement from the group said "all parties" should refrain from instigating violence and said ASEAN stood ready to help.
ASEAN groups Myanmar, Singapore, the Philippines, Indonesia, Thailand, Laos, Cambodia, Malaysia, Brunei and Vietnam.
The bloc's effort to engage with Myanmar's military has been criticised by supporters of democracy, with a committee of ousted Myanmar lawmakers declaring the junta a terrorist group and saying ASEAN's engagement would give it legitimacy.
Sa Sa, the committee's anointed envoy to the United Nations, said ASEAN should have no dealings with "this illegitimate military-led regime".