Stellini, 48, was appointed on 26 March after Antonio Conte's 16-month spell as Spurs boss came to an end.

Ryan Mason, who worked under Stellini and took charge when Jose Mourinho was sacked in 2021, succeeds him.

Sunday's defeat at Newcastle, where they trailed 5-0 after 21 minutes, was a significant blow to Spurs' hopes of securing Champions League qualification.

"It was devastating to see," added Levy.

"We can look at many reasons why it happened and while myself, the board, the coaches and players must all take collective responsibility, ultimately the responsibility is mine."

Tottenham are fifth in the Premier League table, six points behind both Newcastle in third and Manchester United in fourth.

Both teams have played fewer games than Spurs, who host Erik ten Hag's side on Thursday.

Spurs won one, drew one and lost two games after appointing Stellini, who acted as Conte's assistant during his time as manager.

Stellini also led the side when Conte was missing from the touchline after a gall bladder operation in February, with Spurs winning three of their four Premier League games in Conte's absence, but also losing to Championship side Sheffield United in the FA Cup.

"Cristian stepped in at a difficult point in our season and I want to thank him for the professional manner in which he and his coaching staff have conducted themselves during such a challenging time," said Levy.

Former Spurs and England midfielder Mason, 31, returns to the helm for the final six games of the season.

"Ryan knows the club and the players well," added Levy.

How it 'went so badly' under Stellini

Stellini apologised for the defeat at Newcastle, saying the performance was "unexpected".

He changed the system to a back four for the first time this season but returned to three centre-backs after 23 minutes when he substituted midfielder Pape Sarr with Davinson Sanchez.

The thrashing was Spurs' heaviest Premier League defeat since December 2013, when they lost 5-0 to Liverpool at White Hart Lane.

"It went so badly because we were not prepared enough to play an important match," Stellini told Sky Sports.

"We have a good squad but today no-one showed how good we are. It was my responsibility to decide how we play and we decided to do it differently because of the injuries. It is my responsibility, I took it and it was wrong.

"I have to take responsibility because once we changed system we played better, scored and showed fight. It's very difficult to understand why the first 25 minutes were so bad."

Stellini's tactical decisions had drawn the ire of Spurs fans during his brief tenure, particularly when Sanchez was brought on as a substitute in the 35th minute during the 3-2 defeat against Bournemouth and then booed when he was taken off in the 58th minute.

Spurs are searching for their fourth permanent manager in four years since Mauricio Pochettino left in 2019.

Questions over the playing style have persisted under Stellini, with Spurs conceding nine goals across their last two league matches, the most they've conceded in consecutive league games since May 2003.

'If you are the owner, you are accountable'

Ramon Vega, former Spurs defender on BBC Radio 5 Live

"Issues have been accumulating for weeks, months and years.

"It sums up this club for the past 10 years. The recruitment side is a shambles and the players are not playing like they are supposed to play - you can see that the dressing room is completely split, there's no spirit in this side whatsoever."

On Tottenham chairman Daniel Levy:

"If you are the owner, you are accountable for what happens within the club. You need to make sure all the tools are being given to the management for the football side.

"But the problem is that the whole recruitment has been a shambles for years, from the top to the bottom all the way to the academy and they've wasted a lot of money in that time.

"I think the fans are fed up. They don't see football any more, they don't see excitement, they are not winning anything for a long time.

"And I think Levy needs to take accountability. He made mistakes because he made decisions. He doesn't leave many decisions to the football people and he doesn't recruit the right people."