Volkswagen's supervisory board agreed on Tuesday evening to remove two seats from the carmaker's 12-person management board, three people familiar with the matter said on Wednesday, adding that a decision was not yet finalised.

The news comes a day ahead of a planned leadership change at Europe's largest carmaker that will see Porsche AG Chief Executive Oliver Blume also taking over as Volkswagen CEO from Herbert Diess.

The move signals a sharper focus under Blume's leadership following Diess' turbulent four-year tenure that saw the board swell to its current level.

Overall, the reshuffle would reduce the total number of seats on the management board to nine from 12 and remove the positions in charge of procurement and sales, one of the people said.

Volkswagen's supervisory board discussed the move in a meeting on Tuesday evening but must still confirm a final decision in writing, the sources said.

Volkswagen declined to comment.

Reuters previously reported that the supervisory board was considering shrinking the number of seats on the management board to eight or nine.

The appointment of the 54-year-old Porsche CEO to the helm of the Group reflects efforts by Volkswagen's controlling shareholder families to keep the group on a shorter leash and have greater say over strategy, sources have told Reuters.

Preliminary steps to list Porsche on the stock market, a move which would further solidify the families' control, are expected in coming days, according to sources familiar with the matter, triggering an announcement of an initial public offering as soon as the first week of September.