Brazilian national flag is seen behind Embraer jets at the company's plant in Sao Jose dos Campos, Brazil, December 23, 2017. REUTERS/Leonardo Benassatto

(Reuters) - Brazil's defense minister voiced opposition on Thursday to selling control in Embraer SA EMBR3.SA to Boeing Co BA.N, saying the defense operations of the Brazilian planemaker cannot be separated from the commercial business.

Boeing and Embraer said last week they were discussing a “potential combination”, in a move that would consolidate a global passenger jet duopoly provided Brazil’s government gives its blessing. The companies have given no further details.

Defense Minister Raul Jungmann said on Thursday the ministry was concerned that the negotiations between the aerospace companies had advanced without its knowledge.

“No country in the world would release its grasp on control of a company like (Embraer). It has a nucleus of defense that is inalienable,” Jungmann told reporters in Brasilia.

He said the ministry viewed favorably any deal that maintained local control of the company and would direct its representative on the Embraer board to seek further information. The Brazilian government holds veto power over strategic moves at Embraer.

President Michel Temer has also said he opposes Boeing taking control of Embraer and that the government could use its golden share in the company to block foreign control. He added he would welcome an injection of foreign capital into Embraer.