Juergen Klopp will walk away from Borussia Dortmund next month as one of the most successful coaches in the club's history - and highly-regarded Thomas Tuchel is widely tipped to take over.

It took Klopp three attempts to get the words out no Dortmund fan wanted to hear at Wednesday's media conference.

The 47-year-old confirmed he is leaving after two Bundesliga titles, a Champions League final appearance and the first league and cup double in Borussia's history during his seven years in charge.

"This is the right time for a change at Borussia Dortmund," said an emotional Klopp.

"A big head has to roll - and it's mine."

Having been granted an early release from his contract, which ran until 2018, Klopp's last home match will be against Werder Bremen on May 23.

"It took me a while before I could even say the words," said Klopp, flanked by ashen-faced Dortmund CEO Hans-Joachim Watzke and equally glum director of sport Michael Zorc.

"I wasn't sure until I couldn't answer the question whether I was still the perfect coach for Borussia Dortmund with a clear 'yes'.

"The change will be good for everyone. The club was great when I came and it's still great."

One last dream

He admits he has "one last dream" of beating Bayern Munich in the German Cup semifinal on April 28 to bow out in style at the Berlin final on May 30.

According to German daily Bild and bookmakers, Bwin, Tuchel, one of Germany's rising star coaches, is favorite to succeed Klopp, but Watzke says 'certainty over speed' is the priority in finding the right man.

A quick glance at the table, where Dortmund is 10th, shows how far Klopp's side has slumped since winning back-to-back league titles in 2011 and 2012, then finishing as runner-up to Bayern for the past two years.

Borussia was a mid-table side when Klopp arrived in 2008 before briefly usurping Bayern as Germany's top club in 2012, which was confirmed when the Bavarians were humbled 5-2 in that May's German Cup final.

Following defeat to Bayern in the 2013 Champions League final, Dortmund finished second in the league in 2013 and 2014 until this season's drop off.

Key injuries and a loss of form from its World Cup winners led to dire results which saw Dortmund drop to 17th in December and then last place in February.

Its Champions League exit after home and away defeats to Juventus in the last-16 signaled how far it was from its incredible 4-1 rout of Real Madrid in Dortmund during the 2013 semifinals en route to facing Bayern at Wembley stadium.

The charismatic Klopp, known for his trademark sideline leaps of celebration after Dortmund goals, was suddenly a forelorn figure this season as his team lost repeatedly and its counter-pressing system failed to work.

"But you can be sure that after all this great success and this incredibly good co-operation, you will always have the eternal gratitude of Borussia Dortmund," said an emotional Watzke before hugging Klopp.

As to his future, Klopp insists there has been no contact with any club.

"I'm not tired, I have not planned anything in the background, there will be no sabbatical, unless I am forced to take one, nothing is planned or calculated."

The timing of his announcement is simply to allow Dortmund to plan its future without him.

"I chose this time to announce it because in the last few years some player decisions were made late and there was no time to react," he said in reference, in particular, to Mario Goetze's shock departure to Bayern in April 2013.

German bookmaker Bwin has Premier League club Manchester City, then Arsenal, as his most likely future employers, especially as Klopp speaks good English.

"Juergen Klopp has a good reputation in England," said ex-Liverpool and Germany midfielder Dietmar Hamann.

"I think he would fit in well at Manchester City and they will certainly have talked about him."