British MEPs are powerless to block new laws in Brussels even when they unite across party lines, research has found.
UK politicians have been outvoted in the European Parliament on 84% of motions that the majority of them opposed, according to a Business for Britain report.
It warned that Britain can only stop legislation by making large alliances but such a move is "impractical" when so many MEPs are committed to greater European Union integration.
The cross party group, which is campaigning for a better deal from Brussels, found that a majority of British MEPs voted against 576 of the 1,936 motions put before the European Parliament in the last Parliamentary session, which ran from 2009 to 2014, but 485 of them still passed.
Most defeats were on motions related to budgetary control, employment and social affairs, agriculture and regional development.
The study claims the UK, which has 73 seats, is one of the most under represented states for its population size with British MEPs representing around 880,936 each compared to their counterparts in smaller countries, such as Luxembourg which has around 70,900 voters in each constituency.
Germany has the most seats at 96, France holds 74, Italy has 73 and Spain holds 54.
Robert Oxley, campaign director of Business for Britain, said: "Despite turnout for EU elections plummeting to new depths, the European Parliament has become more powerful and more committed to advocating values that are often in direct contradiction to those of voters in Britain.
"British MEPs must either toe the line of large pan-European alliances that are committed to further political union or fruitlessly vote against legislation that they are unable to block. Reforms are needed to protect member states from the tyranny of a legislature that their elected representatives have no chance of blocking, even when they unite across party political lines."