The German giants will sell their top scorer, but only if Chelsea move quickly (Picture: Getty)

Borussia Dortmund have warned Chelsea they are fast running out of time to sign Pierre-Emerick Aubameyang, with just ‘days’ left until their deadline for bids expires.

The Blues emerged as late suitors for the Gabon international after being gazumped in the race to sign Romelu Lukaku by Manchester United, while AC Milan are also thought to be keen.

Dortmund have consistently said that Aubameyang would be allowed to leave if their €70 million (£61.6m) asking price was met, though have always insisted that the deal must be completed well in advance of the new season to give them time to find a replacement.

READ MORE: Are the Premier League’s big guns making a mistake by overlooking Pierre-Emerick Aubameyang?

And CEO Hans-Joachim Watzke has reiterated that stance, telling Chelsea they will only wait a few more days to receive a suitable offer before they will rule out his sale entirely.

Speaking to German newspaper, Wel am Sonntag, Watzke said: ‘We have told Auba if he wants to move somewhere, and if he has a club willing to meet our demands, then come to us and we’ll talk.

Aubameyang has been getting fans excited with his blue-themed posts on Instagram (Getty)

‘But this will only apply within a certain time window, which is slowly closing. We would clearly need to get a replacement for him, which is difficult to impossible in any event.

‘We will wait for a couple more days, but not for much longer. There are no offers on the table for him so far.’

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Watzke also conceded that Aubameyang would likely earn a more lucrative salary were he to leave, adding: ‘There are a few clubs on this planet where he can obviously earn more.’

Aubameyang was the top scorer in the Bundesliga last season, edging out Bayern Munich star Robert Lewandowski, with 31 goals in 32 appearances domestically.

Chelsea are in need of a new frontman after Antonio Conte told Diego Costa he no longer featured in his plans, though almost two months later they are still searching for a replacement after Lukaku picked United.

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