A cross–party group of MPs is urging the Foreign Office to support a corruption whistleblower who says he is the victim of “political persecution” in Monaco. Margaret Hodge, a former Labour minister, Andrew Mitchell, a former Tory minister, and other politicians are calling on the foreign secretary, Dominic Raab, to help Jonathan Taylor, a 51-year-old British lawyer who was recently arrested while on holiday in Croatia. He was arrested at the request of the authorities in Monaco. The MPs are pressing the British government to help bring Taylor back to the UK because of the “high-level corruption” he has exposed. Taylor, from Hampshire, has been ordered to remain for weeks in Croatia as he faces extradition to Monaco. Eight years ago Taylor blew the whistle while working for a Dutch multinational firm, SBM Offshore, in Monaco. He helped reveal how the Monaco-based firm had paid large-scale multimillion dollar bribes to secure contracts in the oil industry around the world. His information helped prosecutors in the Netherlands, the US and Brazil to force SBM to pay huge penalties to settle the corruption allegations after admitting its wrongdoing. Three weeks ago, he was arrested at Dubrovnik airport when he arrived there with his wife and three teenage children for a holiday. Croatian legal papers seen by the Guardian show he was arrested at the request of the public prosecutor in Monaco for alleged “bribery/corruption” committed in 2013. It is understood that this allegation relates to a complaint from SBM Offshore that Taylor attempted to extort money from the firm when he was negotiating compensation for leaving the company. The firm had alleged that he threatened to inform prosecutors about the corruption unless he was given more money. Taylor denies the allegation, adding that a court in Monaco threw out the extortion claim two years ago. He said he was the victim of “clearly political persecution” by the Monaco authorities in what amounted to “a form of revenge”. A Croatian court has released Taylor on bail but told him to remain in the country while the extradition proceedings are resolved. His case has been taken up by Hodge, Mitchell and other MPs on the all-party parliamentary group on anti-corruption and responsible tax. In their letter to Raab on Friday, they called on the UK government to help Taylor who they said was “facing international retaliation”. They wrote: “The public rely on the bravery of whistleblowers but far too often, they suffer from vengeful action by their former employers. To encourage whistleblowers to speak out they must be given the appropriate protection. Failure to do so would make others less willing to come forward to expose serious crimes and so undermine the fight against corruption.” An FCO spokesperson later said: “We are supporting a British man and his family following his arrest and detention in Dubrovnik, and are in contact with the Croatian authorities.”