The sun lights the exterior of the New York Stock Exchange, July 16, 2008. REUTERS/Chip East

(Reuters) - A U.S. overhaul of insider trading investigations is due to be agreed as early as this week as regulators address growing concerns about illegal activity on global markets, the Financial Times reported Sunday, citing people involved in the talks.

The plan is likely to be submitted to the U.S. Securities and Exchange Commission (SEC), which will remain the main markets watchdog responsible for enforcing federal securities laws, the newspaper said.

However, the new system would reform the way stock exchanges handle cases they refer to the SEC, the newspaper said.

Under the proposed measure, the nine U.S. stock exchanges that now monitor insider dealing will cede their authority to two bodies, the New York Stock Exchange’s regulatory arm and the Financial Industry Regulator Authority (FINRA), which oversees broker-dealers, the newspaper reported.

The SEC, NYSE and FINRA did not immediately return calls seeking comment.

This shift to a more centralized system should lead to faster and more efficient oversight of illegal activity at a time when the potential for abuse is becoming more widespread, the newspaper said, citing people involved with the talks.