The Organization for Economic Co-operation and Development (OECD) has warned the UK over leaving the European Union.
The inter-governmental body said in a study presented in London Wednesday that there is no advantage to Brexit for Europe and the UK.
If Britons support leaving EU in a June 23 referendum, then they will be financially worse as Brexit could have a stronger impact, OECD said, adding there is "no upside" in it anyway.
"The UK is much stronger as a part of Europe, and Europe is much stronger with the UK as a driving force. There is no upside for the UK in Brexit," said OECD secretary-general Angel Gurria.
The OECD’s warning was issued in the wake of earlier ones the G20, the International Monetary Fund, and US President Barack Obama,
"In some respects, Brexit would be akin to a tax on GDP, imposing a persistent and rising cost on the economy that would not be incurred if the UK remained in the EU,” said the organization.
Brexit campaigners responded by saying the OECD is "making every possible worst case assumption" and the warnings were "just wrong."
“Gross domestic product (GDP) would be 3.3 percentage points smaller by 2020 if Britain left the EU than if it stayed, and 5.1 points smaller by 2030,” according to AFP.
EU membership has long been a hot topic in Britain, where voters are set to go to the polls on June 23 in a referendum to decide whether to leave the 28-nation bloc or stay in it.