Prime Minister David Cameron on Saturday stepped up his campaign for Britain to remain in the EU, warning that exiting the bloc would cost Britain billions of pounds in investment.
Both Cameron and Jeremy Corbyn, leader of main opposition Labour Party, were each out on the Remain campaign trail in search of voter support, as was leading Leave campaign member Boris Johnson, an MP within the prime minister's Conservative party and recently the London mayor.
Johnson will be speaking in the southwest of England, while a rally in the northwest will see Conservative former cabinet minister Owen Paterson argue that a vote to remain will consign Britain "to being a colony of an EU Superstate".
With less than six weeks to go before the June 23 vote, the Remain and Leave camps are neck-and-neck at 50 percent each, according to the What UK Thinks website's average of the last six opinion polls.
The official Britain Stronger In Europe campaign said that it is staging 1,000 pro-Remain events across the UK on Saturday, with Liberal Democrat leader Tim Farron and the Greens' Caroline Lucas also among those taking to the streets.
"This is bigger than party politics," Cameron said.
"Its effects will last longer than our lifetimes. So we are saying with one voice: make sure Britain is stronger, safer and better off -- and vote to remain in a reformed European Union."
Even so, Corbyn was set at a rally in London to attack the Conservatives, arguing that responsibility for many of the country's problems "lies in 10 Downing Street, not in Brussels".
Cameron added in a statement Saturday that a vote for Brexit would mean an end to Britain's membership of the European Investment Bank, which in the past three years has given more than £16 billion ($23 billion, 20 billion euros) for UK projects.