Zimbabwean President Robert Mugabe has not been invited to the Commonwealth summit meeting, to be held in Nigeria.
Mr Mugabe's attendance would see boycotts by other nations
"He will not have an invitation," said Nigerian President Olusegun Obasanjo, who hosts the summit next month.
Zimbabwe was suspended from the group of 54 mainly former British colonies after charges that Mr Mugabe rigged his re-election last year.
Britain and Australia said Mr Mugabe should not be invited, but the hosts had the final say.
Mr Mugabe had said he expected to attend, raising the threat of a boycott by Britain's Queen Elizabeth and by prime
ministers of Britain, Australia, Canada, New Zealand and
"If there is no invitation they [Zimbabwe] will not come," Mr Obasanjo told journalists at a briefing at his residence near Lagos.
The summit runs from 5-8 December in Abuja, Nigeria's capital.
A spokesman for Zimbabwe's ruling party, Didymus Mutasa told the BBC that he now expected a number of other southern African countries to boycott the occasion.
BBC diplomatic correspondent Barnaby Mason says that according to recent comments by Commonwealth officials, it simply was not possible to invite Mr Mugabe to the summit.
Zimbabwe's suspension could be lifted only by the summit itself or by the three leaders - of Nigeria, South Africa and Australia - who had the issue delegated to them last year.
Obasanjo will not want a huge row over Zimbabwe at the summit
The trio were deadlocked, with South African President Thabo Mbeki in favour of readmitting Zimbabwe and his Australian counterpart, John Howard, adamantly opposed.
The South Africans have been promoting talks between the ruling party and the opposition in Zimbabwe with the hope of producing a deal in time for the summit.
President Obasanjo went to talk to both sides last week.
While he was in Zimbabwe, President Mugabe embarrassed him by saying at a joint public appearance that he was looking forward to going to Abuja.
Mr Obasanjo said only that he was still consulting.
The dispute has got tangled up with another over the possible readmission of Pakistan, suspended after General Musharraf's 1999 military coup.
The UK and Australia have pushed for letting Pakistan back in, but African countries have rejected the idea.