"It is disappointing," Commonwealth spokesman Joel Kibazo said on Monday. "What we want is the return of Zimbabwe into the Commonwealth."
"What we care about is the welfare of the people of Zimbabwe and that is what we will continue to do," Kibazo added.
Harare opted out of the 54-nation body of mainly former British colonies on Sunday after Commonwealth leaders decided to extend the suspension of the southern African state.
Zimbabwean President Robert Mugabe said the decision was "unacceptable" and made good on his earlier threat to quit the group.
Zimbabwe was suspended from the Commonwealth in March last year after a presidential election in which the 79-year-old Mugabe was voted back into office amid allegations of rigging, violence and political repression.
"It is disappointing. What we want is the return of Zimbabwe into the Commonwealth"
The Zimbabwe information ministry said Mugabe had announced his country's exit to the presidents of Nigeria, South Africa and Jamaica who had telephoned him to inform him of the decision.
Whilst voting to punish Mugabe, the Commonwealth will none the less continue to push for reforms.
The Commonwealth has asked Nigerian President Olusegun Obasanjo to make a first hand assessment of democracy and human rights in Zimbabwe. He is planning to visit the southern African nation soon, a Commonwealth statement said.
This year's summit saw members of the so-called "white Commonwealth", including Britain which advocated a tough line on Zimbabwe, taking on countries like South Africa which wanted it to be reinstated immediately.