“And it seems very fair that it will be resolved in favour of the Portuguese position,” Fernandes said in Porto on the sidelines of a ceremony for the Green Project Awards (GPA2016), held in the Serralves Foundation auditorium.

According to the Environment Minister, Portugal filed a complaint about the Spanish facility a week ago, and “it is natural that the European Commission will [now] want to hear from the Spanish State,” and it is likely that nothing will be requested from Portugal, “in the next 90 days.”

According to legal experts, the complaint to the commission is likely to have little more than symbolic value, given that it will take a long time to review it, and Spain will not be required to suspend the project in the meantime.

Fernandes has said that Portugal asked the commission to suspend all acts leading to the construction of the waste facility, but on Monday Spain's secretary of state for the European Union said that Spain would "in the coming days" start work on the facility, which the Spanish government has said will be safe.

The Almaraz plant has been in operation since the early 1980s. It is located on the River Tagus, which flows from spain into Portugal.

Environmentalists have warned that the plan to build the facility almost certainly indicates that Spain intends to extend the life of the Almaraz power plant beyond the current horizon, of 2020, and have called on the Portuguese government to take a firmer position on the matter. At a demonstration in front of the Spanish consulate in Lisbon on the day of the Madrid meeting, protestors went so far as to call for Fernandes's resignation.

The Spanish government has said that no final decision on extending the life of the Alamaraz plant has yet been made.