One of the nine Australian men who stripped down to his swimmers at the Malaysian Formula One Grand Prix has resigned from his position in the office of Cabinet Minister Christopher Pyne.

Senior policy advisor Jack Walker gave notice to the Defence Industry Minister on Saturday, shortly after flying back to Australia.

“Jack indicated to me his deep regret for causing any embarrassment to the Government and apologised,” Mr Pyne said in a statement.

“One lapse of judgement does not detract from the fact that Jack has been an outstanding staff member, a significant contributor to my office since late 2013 and I believe he will have a bright future.”

Pyne says Walker offered his resignation. Photo: AAP

Finance Minister Mathias Cormann said the 26-year-old had paid a high price for the incident.

“I hope he has a great and successful career moving forward, and we certainly wish him all the best, and I feel a bit sorry for him,” Senator Cormann told Sky News.

Mr Walker and eight other Australians were placed in custody for four nights after last weekend stripping down to their swimmers while celebrating Daniel Ricciardo’s win at the Malaysian Grand Prix.

For several minutes the group chanted and drank beer which they had poured into their shoes, while wearing swimmers that had been emblazoned with the Malaysian flag.

The group of friends, mostly from Sydney, were let off with a caution in Sepang Magistrates Court on Thursday.

Earlier the Prime Minister had suggested Mr Walker would be considering his future working in the government.

“Certainly the young man involved needs to have a very hard look at himself and I’m sure he will be considering his future carefully,” Malcolm Turnbull said.

Other group members Branden Stobbs, 29, Edward Leaney, 25, Nicolas Kelly, 27, Thomas Laslett, 28, Thomas Whitworth, 28, James Paver, 27, Adam Pasfield, 25 and Timothy Yates, 29, also arrived home on Friday.