UBS, JP Morgan Chase, Citibank, HSBC and the Royal Bank of Scotland have collectively been fined £2 billion by US and UK regulators for manipulating the foreign exchange market (forex).

The forex is a global market for trading currencies with the main participants being the world’s largest financial institutions. $5.3 trillion is traded daily on the forex which is significantly more than either the stock or bond market. Approximately 40% of the world’s forex trading happens in London.

The Financial Conduct Authority fined the five banks £1.1 billion. Whilst U.S regulator the Commodity Futures Trading Commission (CFTC) fined the same five banks a further £900 million.

Barclays have also been under investigation, however, they decided to pull out of the settlements talks at the last minute. A company spokesman said it “concluded that it is in the interest of the company to seek a more general coordinated settlement.

Following their year long investigation the CFTC concluded a number of traders coordinated their trades to manipulate their foreign exchange benchmarks. To communicate traders developed a unique code and passed information to one another via internet chat rooms. The manipulation occurred between January 2008 and October 2013.

The Serious Fraud Office is now in the process of preparing a legal case against the traders central to the manipulation.