The US banker Morgan Stanley’s German country head has stepped down from his post over a probe for his role in the federal state of Baden-Württemberg’s purchase of a stake in a German utility EnBW in 2010.

Declining to disclose details about the departure, Morgan Stanley was quoted by Financial Time as saying, "Dirk Notheis is no longer a member of the board."

The market regulators are investigating Notheis breach of trust, when he advised to his friend Stefan Mappus, a former state governor, over the state’s acquisition of a 45% stake in EnBW from EDF, the French utility.

The deal has been agreed without obtaining approval from lawmakers, highlights the suspicious role imparted by Notheis, said the prosecutors.

According to Prosecutors, Mappus was believed to have "caused financial damage to the state" by accepting a purchase price of EUR840m that was too much for the stake, and failing to involve the regional parliament in the decision.