Borussia Dortmund have confirmed that striker Robert Lewandowski will not be signing a new contract with the Bundesliga champions.

It has long been expected that the Poland international would opt against extending a deal that has less than 18 months remaining. With Manchester United and Bayern Munich strongly linked to the 24-year-old, the questions will now turn to which club Lewandowski will join, and when.

“Either he goes in June or he stays another year,” said Dortmund sporting director Michael Zorc, according to ESPN. “We will have to see if he is going to be on the move in the summer.”

Despite Zorc’s comments, it would be a significant surprise were Dortmund to resist Lewandowski’s sale this summer and instead lose him for nothing the following year.

United had previously appeared the frontrunners for Lewandowski’s transfer, having pursued he player last summer, but in recent weeks there have been strong reports that Bayern were already in negotiations.

Dortmund manager Jurgen Klopp does not believe that there is already a deal in place.

“Nothing is decided,” he said. “I don’t know what the actual situation is.”

There has also been gathering rumors of late suggesting that Manchester United are keen on Roma star Erik Lamela. The 20-year-old has been a key performer in Serie this season, following his move form River Plate in the summer of 2011. Lamela, a left-footed forward, who primarily plays from the right, has scored 11 goals in 21 league appearances this campaign.

But Lamela’s agent Pablo Sabbag has said that there is little substance to the speculation, although he wouldn’t rule out a move for his client.

“No, there is no truth,” he told Gazzetta Giallorossa.

"At the moment there is no official offer from Manchester United for Lamela.

"I have a relationship with Manchester United, but I have never discussed this topic with them or with Roma.

"Will Erik stay at Roma? It is still too early to talk about the market."

Lamela is not the only Argentinian winger to be linked with United of late, with reports persisting of an interest in Real Madrid’s Angel Di Maria. The Daily Express reports that the 25-year-old has been offered to several clubs, amid claims in Spain of a falling out with manager Jose Mourinho.

It is believed that Paris Saint-Germain are also considering bidding for the former Benfica man.

Finally, United are also listed as one of several top clubs pursuing highly rated Schalke midfielder Julian Draxler. German publication Bild reports that Manchester City, Arsenal, Chelsea, Milan, Internazionale and Real Madrid have all expressed an interest in the 19-year-old.

Schalke’s general manager, Horst Heldt, has confirmed that several inquiries have been made for the Germany international.

“There have long been reports of interest from international clubs,” Heldt said, according to Bild. “And now we have also had inquiries for Draxler.

“But this is not an issue for us. A sale is not up for discussion.”

Draxler’s agent, though, suggested that a move was not out of the question this summer. With Schalke struggling in the Bundesliga this season, a move to a European giant may prove tempting for the player.