LONDON (REUTERS) - The co-founder of fashion brand Superdry is donating £1 million (S$1.7 million) to the campaign for a referendum on the final Brexit deal, the Observer newspaper reported on Saturday (Aug 18), as pressure intensifies on Prime Minister Theresa May.

"I'm putting some of my money behind the People's Vote campaign because we have a genuine chance to turn this around,"said Julian Dunkerton, a "remainer" who opposes Britain's planned departure from the European Union.

"I've got a good instinct for when a mood is going to change and we're in one of those moments now."

Britons voted in a 2016 referendum to leave the EU but in July the proportion of voters who favour a referendum on the final terms of any Brexit deal overtook those who do not for the first time, according to opinion polls.

London and Brussels hope to agree a Brexit deal at a summit in October but May faces splits within her party and the tough task of securing parliamentary approval for the final agreement.

Campaigners on both sides of the argument have been stepping up their efforts in recent weeks as some Brexiteers argue against any agreement which keeps Britain tied to European Union mechanisms such as the customs union or single market.

On Saturday, the former leader of the United Kingdom Independence Party Nigel Farage said he would join a "battle bus" tour around the country by a pro-Brexit group which is opposed to May's plans, arguing it makes too many concessions to Brussels.

Both Britain and the European Union have said they want to avoid a damaging "no deal" outcome which would be particularly harmful to businesses.

"It is the responsibility of the EU to ensure its consumers and businesses are not harmed," Brexit minister Dominic Raab was quoted as saying by The Sunday Telegraph newspaper.

"Securing a deal is still by far the most likely outcome, but we want to make sure that we clearly set out the steps that people, businesses and public services need to take in the unlikely event that we don't reach an agreement."

The paper said the government is planning to recognise some EU regulations if London and Brussels fail to strike a deal, taking a "flexible" approach to make sure medicines, car parts and chemicals are still available.

A spokesman at May's Downing Street office did not offer an immediate comment on the report.