European regulators sent letters of objection on Tuesday to JPMorgan Chase, Crédit Agricole and HSBC for having colluded to rig benchmark interest rates tied to the euro. Authorities at the European Commission said that this was the first formal step toward investigations into antitrust activities at the three banks. The three banks are accused of colluding to influence the pricing of interest rate derivatives tied to the Euro Interbank Offered Rate, or Euribor. The move is the second time the commission has pulled up banks for rigging interest rates. In December 2013, the commission fined eight financial institutions $2.3 billion on similar charges. Four banks -- Barclays, Deutsche Bank, Royal Bank of Scotland and Société Générale -- were found to have participated in a cartel involved in financial products linked to the Euribor. "Since that time, we have continued our investigation under the standard cartel procedure for the three parties that did not settle with the Commission -- namely Crédit Agricole, HSBC and JPMorgan Chase," a statement from the commission read. The European Commission said that after a preliminary investigation, it has determined that the three banks named Tuesday were also involved in the cartel breaching the EU's antitrust laws. The banks will be given adequate time to make their cases, after which a final decision will be made. "JPMorgan Chase has cooperated fully with the European Commission throughout its investigation," a bank spokesman said. "The company believes that the statement of objections is without merit and intends to defend itself fully." "The commission has only just now announced that it is sending the objections," said Louise Tingstrom, a Crédit Agricole spokeswoman. "We shall examine them as soon as we have received them." Euribor and other benchmark interest rates help determine the borrowing costs for trillions of dollars in loans, credit cards and mortgages. A company found to have broken EU antitrust laws can face fines up to 10 percent of its global revenues.