On the second anniversary of the UK's Brexit referendum, tens of thousands of pro-EU demonstrators marched to the British parliament in London on Saturday to demand a vote on the terms of the final Brexit deal.

Rather than a second Brexit referendum, campaigners were calling for a "people's vote," to approve the final deal Prime Minister Theresa May makes with the EU.

Read more: EU Customs Union, Single Market, Brexit — What you need to know

The march was attended by pro-EU politicians from a wide range of political parties, including the main opposition Labour Party, the Liberal Democrats and some members of May's Conservatives.

A smaller counter-march by Brexit supporters was also held in London.

"Whatever your opinion on Brexit, no one would disagree that it's a big deal. And not a done deal," the People's Vote campaign said ahead of the march.

Read more: Opinion: 2016 - Lies, propaganda and calamities

The group urged supporters to "ensure that we, the people who will be affected by the government's Brexit negotiations for generations, have a People's Vote on the final Brexit deal."

The UK is yet to define exactly what it wants in its future relationship with the EU.

A number of major businesses, including banks and auto makers, have said that a failure to reach free-trade agreement  could disastrous for them.

Plane-maker Airbus has warned it might pull out of the UK, where it employs about 14,000 people, if no trade deal is made with the EU. Similarly, tech giant Microsoft has said the potential import tariffs on goods means it may have to reconsider future expansion in the UK. Most recently, BMW has warned it could cut operations.

Brexit-backing government ministers such as Boris Johnson have called for a clean break from the EU to allow Britain to strike new trade deals around the world. In an article in the Sun newspaper on Saturday, Johnson wrote that any softening of the final deal would be unwelcome. 

Johnson was quoted in the Telegraph newspaper by two diplomatic sources as dismissing, in vulgar terms, the concerns of business leaders about the impact of Brexit. 

Jurgen Maier, head of Siemens in Britain, told the BBC in an interview that slogans about Brexit were "incredibly unhelpful." He suggested instead getting closer to European states to work out what a "realistic, pragmatic Brexit is, which works for both sides."

The second anniversary of the referendum was also marked elsewhere in Europe, with the organizers of one pro-EU march in Berlin claiming to have attracted 1,000 participants.

law/jm (AFP, AP, dpa Reuters)

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