Media playback is unsupported on your device Media caption Emily Thornberry MP: "It's incumbent on our authorities to look into this"

An MP is calling for a Serious Fraud Office probe into the financial affairs of Formula One chief Bernie Ecclestone.

It comes as a seven-week civil case over an £85m ($140m) damages claim against the billionaire, 83, concludes.

He denies making corrupt payments to facilitate the sale of F1, and says he paid a German banker £10m because he was threatened over his tax affairs.

Shadow attorney general Emily Thornberry told BBC Newsnight that UK authorities had a duty to investigate.

The Labour MP said: "We cannot just walk away from this case. It does seem to me that we have a duty to investigate this. What is the Serious Fraud Office for if not for investigating cases like this?"

'Blackmail victim'

Mr Ecclestone is the chief executive of F1 and has ruled the sport for almost four decades. He is the long-time commercial rights holder of F1, but sold off a majority of the ownership in the 1990s.

In the High Court case, due to finish on Friday, Mr Ecclestone stands accused of a "corrupt agreement" with German banker Gerhard Gribkowsky and of conspiring to deliberately undervalue F1 when it was sold in 2006 to private equity group CVC, in order to retain control of the sport.

German media giant Constantin Medien had an interest in the sale of a stake belonging to then-F1 shareholder Bayern LB, and is claiming damages of £85m, plus interest.

Gribkowsky, a former executive at Bayern LB, was convicted in a Munich court last year of corruption charges after pleading guilty to accepting £27m in total from Mr Ecclestone and Bambino, an off-shore Ecclestone family trust.

Media playback is unsupported on your device Media caption Dan Roan reports for Newsnight on the questions Bernie Ecclestone faces

Gribkowsky confessed to taking bribes and was jailed for eight-and-a-half years.

Mr Ecclestone admits paying Gribkowsky but denies it was bribery, claiming he was effectively the victim of blackmail.

He insists Gribkowsky threatened to "shake him down" over his family's tax affairs and to falsely accuse him of tax evasion by suggesting Mr Ecclestone was in control of Bambino, something he strongly denies.

In July, German prosecutors indicted Mr Ecclestone on a bribery charge and a panel of judges are yet to decide whether he must stand trial in Munich. Since then Mr Ecclestone has had to defend himself in the High Court case, with a judgement expected in the new year.

Mr Ecclestone also faces bigger damages claims from Bayern LB and another from a private equity firm in the US, as well as potential criminal proceedings in Switzerland.

Ms Thornberry, MP for Islington South and Finsbury, first wrote to Attorney General Dominic Grieve about Mr Ecclestone's financial affairs in 2011, when he appeared as the star witness in Gribkowsky's trial.

"I got letters back which weren't terribly informative to say the least... so we're two years down the line and I'm very disappointed that it doesn't seem as though the British authorities are taking this as seriously as they should be," she said.

Image caption Bernie Ecclestone gave evidence at the start of the hearing

"It's really important for the reputation of this country that people know that we don't rely on prosecutors around the world to prosecute our citizens if our citizens have done something wrong. We should be able to prosecute our own people and do it properly."

'Questions raised'

The MP added: "All I can say is that from what we've seen in the German courts and the British civil courts, there are questions to be answered. There should be proper investigation by both the Serious Fraud Office and by HMRC about Bernie Ecclestone and as far as I can see that isn't happening.

"Whatever happens in Germany I want to know what's happened in this country... I asked them two years ago... and as far as we can see nothing much has happened."

During the High Court case, Donald MacKenzie, the co-chairman of CVC, claimed that Mr Ecclestone had apologised to him for forgetting to tell him about the payment to Gribkowsky.

Ms Thornberry said: "I do think it's really quite remarkable."

An SFO spokesman told Newsnight: "The SFO is fully aware of the ongoing investigations in Germany into Bernie Ecclestone."

HMRC said it could not comment on an individual case because of strict rules on taxpayer confidentiality.

Mr Ecclestone declined to comment, saying it would be inappropriate before the judgement in the civil case.

You can also watch Dan Roan's Newsnight film in full on the BBC iPlayer.