March 12 (Reuters) - The Federal Reserve Bank of New York looked at whether a key foreign-exchange benchmark was subject to manipulation in 2012 but did not pursue any public action, the Wall Street Journal reported, citing people familiar with the matter.

The benchmark - the WM/Reuters fix - relates to several exchange rates, including the euro, sterling, Swiss franc and yen. They are compiled using data from Thomson Reuters and other providers, and are calculated by WM, a unit of State Street Corp.

The largely unregulated $5.3 trillion-a-day currency market has become a focus of a probe into alleged collusion between dealers at some of the world's biggest banks.

The so-called fixings, which are used to price trillions of dollars worth of investments and deals and are relied upon by companies, investors and central banks, are at the centre of a global investigation into allegations of manipulation by traders.

Last week, the Bank of England revealed that allegations of rigging of world currency markets had been flagged as far back as mid-2006 as it suspended a staff member as part of a probe into what it knew about the alleged manipulation.

The New York Fed's queries started around September 2012 at a time when the scandal over banks' attempted manipulation of the London interbank offered rate, or Libor, was in full swing, the paper reported.

The WM/Reuters fix was one place they looked, when they set out to see whether other benchmarks might be susceptible to similar efforts, a person familiar with the central bank's thinking told the Journal.

The New York Fed carries out the U.S. central bank's market activities.

"In light of the focus on reference rates in other markets, we sought to better understand the various reference rates commonly used in the FX market," spokeswoman Andrea Priest said.

"Accordingly the FXC undertook an effort to catalogue existing rates. This effort did not reflect concerns specific to the FX rate."