LONDON, Sept. 17 - Prominent British scientists warned on Monday of the impact of Britain leaving the European Union (EU) without a deal, which could affect scientific research immediately and could take years to build.

"Britain has benefited enormously from talent from the EU", and "one reason that UK has done very well in science ... is because it has been so open to talent from all over the world, especially from the EU the last four decades," Sir Venki Ramakrishnan, president of The Royal Society, said at a press briefing.

He was joined by two renowned British scientists and former presidents of The Royal Society, Sir Paul Nurse and Lord Martin Rees, at the event.

Many in Britain's science communities have voiced their concern about the uncertainty surrounding the Brexit process which might affect Britain's scientific innovation and development in the long term.

Britain could lose access to over one billion pounds a year in EU research funding, and even with British government's guarantees, UK-based researchers and small- and medium-sized enterprises will lose access to around half a billion pounds a year in research funding, according to The Royal Society.

The mobility of international researchers after Brexit is another issue. For the time being, one in six academic staff in Britain's higher education institutions are from elsewhere in the EU, figures from the Society show.

Britain's science communities have been calling upon the government to create the lowest possible barriers to practicing scientists seeking to move across borders after Brexit.

"International mobility has always been crucial to science, and the reason is that mobility allows ... exchange of ideas and expertise. If countries are isolated, they tend to do not very well in science," said Ramakrishnan, who is a Nobel Prize-winning biologist.

The Society urges in a press release that science needs a Brexit deal that keeps highly-skilled scientist working in the UK and ensures that international talented people still choose to come here and contribute to Britain's globally competitive science.

"It's not just health, science brings safety standards across countries and cannot be put at risk," said Nurse.