The Republican presidential challenger, who is crushing Barack Obama in the race for cash, will dine with leading bankers, lawyers and former ambassadors in central London on Thursday July 26.
Dozens of supporters will pay $25,000-$75,000 (£16,070-£48,191) a plate for a 6.30 dinner with the former Massachusetts governor or $2,500 (£1,607) to attend a 5pm reception.
At Mr Romney’s side will be Patrick Durkin, his top fundraiser and Barclays’ lobbyist in Washington. Bob Diamond, the bank’s former chief executive, quit the Romney campaign after resigning from the company last week.
They will be joined by senior bankers from Goldman Sachs and HSBC among others, along with executives from the private equity industry in which Mr Romney made his $250 million fortune.
Mr Romney, who was chief executive of the 2002 Winter Olympics, will be in London for the Olympic opening ceremony. A horse owned by his wife, Ann, is part of the US Olympic equestrian team.
The 47 named co-hosts of his London events have been sworn to secrecy by the notoriously tight-lipped Romney campaign. They referred all enquiries to a spokesman, who refused to comment.
One senior lawyer slated to attend, who asked not to be named, told The Daily Telegraph he was supporting Mr Romney because of his “sound business acumen”.
“He’s a guy that can read a balance sheet, knows about creating jobs and really understands about deficits which are all very important things, as people here in the UK also understand,” he said.
Guests are told on their invitations that they must bring copies of their US passports in order to prove that they are eligible under US election law to donate to the Romney campaign.
Thomas Grant, an American law academic teaching at Cambridge University who chairs the British branch of Republicans Abroad, is named as a co-chairman of the events, along with Dwight Poler, the European chief of Bain Capital, the private equity company Mr Romney once led.
Also due to attend is Prof Colleen Graffy, a former senior diplomat in George W Bush’s administration, who prompted controversy in 2004 by describing the suicides of three inmates at the Guantanamo Bay prison camp as a “good PR move”. She now teaches law in London.
Several London-based attorneys from Ropes & Gray, the law firm of Mr Romney’s personal money manager Brad Malt, are also expected. The practice frequently represents Bain Capital.
The events come after Mr Romney’s campaign outraised the President’s for two successive months. Together with Republican headquarters, he raised $182 million in May and June, compared to Mr Obama and the Democrats’ $130 million haul.
Meanwhile Mr Romney’s conservative allies in so-called Super PACs – a kind of external campaign group that can collect unlimited funds from corporations – are also humbling efforts by those supporting Mr Obama.
Eric Varvel, a fellow Mormon who is chief executive of Credit Suisse’s investment bank and is due to attend Mr Romney’s London dinner, has given $100,000 (£64,387) to Restore Our Future, the leading Super PAC backing Mr Romney.
Mr Obama’s allies have accused the Republican of trying to “purchase the White House”, while attacking him for his vast wealth and financial arrangements, which includes holdings in the Cayman Islands and Bermuda and a Swiss bank account that was only recently closed.
One invitee to the London events told The Daily Telegraph: “I don’t think anyone should have to apologise for having worked hard and been successful.
It’s sad that we’ve reached a point where some parts of American politics can characterise that as a bad thing. The American dream, the American understanding of capitalism was built on the idea that hard work gets rewarded.”
The events are being organised by ScottPrenn, a London company specialising in throwing high-profile fundraising events for political campaigns and charities. The firm organised a London event for Senator John McCain in 2008 and another Romney event last year.