OTTAWA, Jan 28 (Reuters) - A North American Free Trade Agreement (NAFTA) panel has halted a probe of Canada's oversight of oil sands tailings ponds following a unanimous vote by its three member countries, officials said on Wednesday.
The vote came even after staff at the panel, the Commission for Environmental Cooperation, had recommended proceeding with a formal investigation in response to complaints in April 2010 from three Canadians and two environmental groups.
The complainants argued that Canada was failing to enforce environmental laws related to alleged leaks from industry tailings ponds into water in northern Alberta.
The commission initially agreed to investigate in December 2013, offering Canada the chance to respond.
Canada has said both the federal government and provincial government in Alberta are enforcing their environmental laws.
Canada argued that the probe would interfere with ongoing provincial court proceedings related to an Alberta resident who requested a review of tailings waste ponds operated by Suncor Energy Inc.
The panel, set up under the North American Agreement on Environmental Cooperation to review complaints raised by citizens and groups about the enforcement of environmental laws, rejected Canada's arguments in July 2014, stating the provincial case was no longer active.
However, with the vote that was held on Tuesday, the three countries shut down the investigation. (Editing by Jeffrey Hodgson and Andre Grenon)