After nearly four years on the run, Michael Brown, the Liberal Democrats' fugitive donor, was finally brought before a British court on Tuesday to be told that he would start serving his seven-year jail sentence immediately.

Michael Brown, who gave the party £2.4m in 2005, was one of Britain's most wanted fraudsters. In a hearing at Southwark crown court, Justice Alistair McCreath told Brown that he must begin his seven-year sentence for theft, furnishing false information and perverting the course of justice straight away, having been convicted in his absence in 2008.

Brown's high-profile return to Britain may prove to be an embarrassment for the Lib Dem leader, Nick Clegg, who has refused to repay the donation, which came exclusively from stolen funds. The party received the donation through Brown's company, 5th Avenue Partners, and it remains the biggest ever received by the party from an individual.

In court, Brown, 46, wearing a grey baggy jumper and jeans, spoke in a Scottish accent to confirm his name.

Brown managed to convince a number of businesspeople that he was a successful investor with connections to royalty and the US secret services. In fact, he was a son of a whisky executive who had few qualifications and was being sought for fraud in Florida. A court was later told that Brown's company was wholly fraudulent and that the donation to the Lib Dems was made only so that he could convince his victims that he was a legitimate and well-connected businessman.

One of his victims was Martin Edwards, the former Manchester United chairman, who handed over $10m.

Brown went on the run in July 2008 while awaiting trial for theft. In the days before he disappeared from his Hampstead home, he changed his name and appearance.

The Guardian disclosed last year that Brown was hiding in the Dominican Republic. Under the name of Darren Nally, he was living in the exclusive resort of Punta Cana with his dog Charlie ? named after the former Lib Dem leader Charles Kennedy.

He was arrested after failing to pay a bill in Punta Cana and spent weeks in a jail in the Dominican Republic. Brown then asked to be deported to Spain, where he arrived over the weekend.

He flew into Britain on Monday on an Easyjet flight from Madrid accompanied by two detectives from City of London Police.

Brown will return to court on 21 May after the counsel for the defence said he had expressed concern about the terms of the European arrest warrant that was used to bring him back.