The European Commission said Thursday that it had fined Barclays, Citigroup, JPMorgan Chase, Mitsubishi UFJ Financial Group and the Royal Bank of Scotland a combined 1.07 billion euros, about $1.2 billion , for their roles in foreign exchange trading cartels.

The penalty followed billions of dollars in fines that various government regulators levied on major banks in 2014 and 2015 over their participation in the manipulation of the foreign currency market.

The commission’s action stemmed from what it deemed to be anti-competitive practices by two cartels that operated from 2007 to 2013 . Previous related investigations by the Justice Department, and by regulators in the United States, Britain and Switzerland, examined criminal misconduct and civil violations and had increased scrutiny of currency trading desks.

“Foreign exchange spot trading activities are one of the largest markets in the world, worth billions of euros every day,” Margrethe Vestager , Europe’s commissioner for competition policy, said in a statement on Thursday. “The behavior of these banks undermined the integrity of the sector at the expense of the European economy and consumers.”