Professor Joachim Milberg, chairman of the board of management of the German car giant, told its employee newsletter BMW Zeitung that vehicle sales this year will be "comparable" with 1998's.
On the loss-making Rover operation, Mr Milberg said that management is making changes proposed by a study on how to turn the unit around, including the complete integration of Rover with the BMW group, as well as raising efficiency and productivity levels.
"Investment and the introduction of flexible working hours are just the beginning of a series of measures," he said. "All of these ... should no longer be talked about but need to be implemented quickly."
BMW will also try to boost sales of Rover models, especially of the Rover 200 and 400.
Bernd Pischetsrieder was replaced by Mr Milberg this month after failing to make a profit at Rover since its purchase in 1994. The management change touched off speculation by analysts and investors that BMW might be acquired in whole or part by another carmaker. General Motors, Ford and Volkswagen are all considered possible suitors.
"One thing's certain - we want to continue to remain independent,'' Mr Milberg declared. "The Quandt family [majority shareholders] has always clearly stated its affinity to BMW and has squashed all these [takeover] rumours."
He went on: "I am convinced that the difficult situation, which we are in ... because of Rover cars, will be overcome quickly."
Mr Milberg said 1998 sales of BMW vehicles were more than 38bn German marks, a growth of more than 8 per cent, which was "excellent". He said: "I am convinced that with our series of products, we are well positioned to achieve comparable results."