The UK is liable to pay €47.5 billion ($56.27bn) to the EU as part of its post-Brexit financial settlement, the bloc's consolidated budget report for 2020 says.
The report says the money is owed under articles to which both sides agreed as part of the Brexit withdrawal agreement. The figure was reported earlier on Thursday by RTE News.
The total is significantly higher than expected. The UK's Office for Budget Responsibility predicted in its March 2018 economic and fiscal outlook report that the bill would be €41.4bn.
An initial amount of €6.8bn is due for payment in 2021, the EU's budget report said, with the rest to be paid later.
A trade and co-operation deal between the UK and EU was struck in December after more than four years of bitter negotiations and mistrust, as Britain ended 47 years of EU membership.
On Tuesday, the EU urged London to consider a Swiss-style free-trade agreement with Brussels on agricultural food to end a post-Brexit "sausage war" over some goods moving between Britain and its province of Northern Ireland.
Tension has increased over trade arrangements for Northern Ireland, particularly for chilled meat, because the province's open border with EU member Ireland is Britain's only land frontier with the EU.