Deutsche Bank and Commerzbank confirmed on Sunday they were in talks about a merger, prompting labor union concerns about possible job losses and questions from analysts about the merits of a combination.

Germany's two largest banks issued short statements following separate meetings of their management boards, a person with knowledge of the matter said, indicating a quickening of pace in the merger process, although both also warned that a deal was far from certain.

"In light of arising opportunities, the management board of Deutsche Bank has decided to review strategic options," Deutsche said in its statement.

Christian Sewing, Deutsche Bank's chief executive, told employees that Deutsche still aimed "to remain a global bank with a strong capital markets business... with a global network."

Sewing said many factors could still prevent a merger and a Deutsche spokesman said the talks were expected to last some time. Commerzbank described the outcome as open.

However, formal disclosure of talks appeared to boost the chances of concluding a deal first floated in 2016 before the

banks opted to focus on restructuring.

The German government has pushed for a combination given concerns about the health of Deutsche, which has struggled to generate sustainable profits since the 2008 financial crisis.

The government, which holds a stake of more than 15 percent in Commerzbank following a bailout, wants a national banking champion to support its export-led economy, best known for cars and machine tools.

Berlin also wants to keep Commerzbank's speciality —the funding of medium-sized companies, the backbone of the economy — in German hands.