Bayern Munich might do better to focus on their midweek last-16 Champions League clash, but with Robert Lewandowski agitating for a new contract, transfer speculation around the Poland striker's future is clouding the issue.

Bayern host Red Bull Salzburg in a Champions League last 16, return-leg tie on Tuesday following a 1-1 draw in Austria.

Unusually for him, Lewandowski has not scored in his last three games and off the field, his future beyond this season appears a little unclear.

Over the weekend, there were reports Manchester United lead a list of Premier League clubs to have contacted Lewandowski's agent Pini Zahavi.

Lewandowski, 33, like fellow Bayern veterans Manuel Neuer, 35, and Thomas Mueller, 32, is out of contract in June 2023.

Yet while Neuer and Mueller have reportedly been told in person that the club want to extend, Lewandowski has not.

Last month, Bayern director Hasan Salihamidzic publically stated that the club do not want to sell him. "It's out of the question. Robert is a very important part of the team".

Yet the news surprised Lewandowski.

"I'm hearing that for the first time," he said.

The Poland international turns 34 in August, but due to his punishing fitness regime, Lewandowski is at the top of his game.

He has hit 39 goals in 34 games in all competitions this season.

In his weekly Bild column, German legend Lothar Matthaeus was shocked Bayern have not already nailed down the future of their top-scorer, who was last December named FIFA's best male player for the second year running.

"When the world's best footballer reveals in front of the camera that he hasn't been told that (Bayern) want to keep him, then I prick up my ears," grumbled Matthaeus.

Before Saturday's draw with Leverkusen, Bayern CEO Oliver Kahn said Lewandowski, like Mueller and Neuer, will be offered a new contract once certain objectives are achieved.

"We now want to concentrate 100 percent on what's at stake: becoming German champions and the second leg against Salzburg. Then we'll take a look," Kahn insisted.

However, Matthaeus believes Bayern's hesitation with Lewandowski could also be down to Erling Haaland hinting he could leave Dortmund before next season.

Kahn has held talks with Haaland's agent Mino Raiola in Monaco.

"Yes, it's true. It's quite normal to meet with a player's agent," said Kahn, who refused to give details.

Having lost David Alaba to Real Madrid on a free transfer last season, Bayern are reportedly eager to avoid the same happening with Lewandowski, who joined on a free from arch rivals Dortmund in 2014.

Bayern estimate Lewandowski's worth to be around 50 million euros ($55 million).

He will be almost 35 when his current Bayern contract expires, but Lewandowski recently told French program "Telefoot" that he wants to keep playing for "at least five" more years.

As well as reported interest from the Premier League, Lewandowski's future is the source of speculation in Spain.

Marca has claimed Bayern are interested in signing 22-year-old Joao Felix from Atletico Madrid which could see Lewandowski move in the other direction to Atletico.

Speculation aside, it is clear Lewandowski will decide where he plays next season.

"With all my experience, I'm calm," Lewandowski replied when asked about a contract extension.

"I'm open to everything, but anything to do with contracts is a secondary issue and stays in the background."

As former Bayern coach Felix Magath put it recently on a Sky talk show, "the player (Lewandowski) is the one who determines what happens, not the club".