Pierre-Emerick Aubameyang has prolonged his Borussia Dortmund contract until 2021, sporting director Michael Zorc has said.

Aubameyang, 28, had been under contract at Dortmund until 2020 but has been linked with an exit for some time, with AC Milan his most prominent suitors.

However, the Gabon international, who topped the Bundesliga scoring charts last season, has now committed to an extension at the Westfalenstadion that is reported to include a pay rise.

"The contract runs through to '21," Zorc told Sky on Sunday. "That's still a long way away.

"One day, he will certainly leave Borussia Dortmund -- he won't end his career here. He's an extremely important player for us, and we continue to plan with him."

Pierre-Emerick Aubameyang has been linked with a Borussia Dortmund exit throughout 2017. STR/AFP/Getty Images

Several publications, including kicker and Bild, have reported that Aubameyang signed the extension some time ago.

On Monday, Aubameyang appeared to confirm the reports when writing on Twitter that listening to music is "better than newspaper."

He added: "It's a bit of time I extend my contract. But it's not your mistake. You didn't know as often."

Let me Listen Music!! better than newspaper. it's a Bit of Time i extend my contract🙈 but it's not your mistake, you didn't know as often ⏰⏰ pic.twitter.com/xtvazSOQgZ — Aubameyang P-E (@Aubameyang7) December 18, 2017

Earlier on Monday, Bild had reported that the new contract was signed in late 2016 but said the striker has Dortmund's assurance that he can leave the Westfalenstadion if a club were to offer a transfer fee in excess of €60 million.

Aubameyang was on target again in Dortmund's 2-1 win over Hoffenheim at the weekend. He has netted 13 goals this season, and a total of 98 in the Bundesliga since arriving from St Etienne in 2013.

He currently ranks fifth in the club's all-time Bundesliga scorer chart, and his tally of 141 in all competitions is only bettered by two players -- Zorc, who scored a total of 159 goals, and Manfred Burgsmuller, who netted 158.

Despite Aubameyang's successes at the Westfalenstadion, he has had issues during his time in Germany, with Zorc telling Sky his punctuality has been a problem.