CME Group Inc , the No. 1 U.S. futures market operator, is again postponing the start of operations in London - its first exchange abroad - due to a technical problem, it said on Friday.

It did not provide a new date.

The 165-year-old exchange is trying to better compete with European rivals such as Germany-based exchange Eurex .

"This notice is to advise you that the launch date for CME Europe Ltd. of 29th September has been delayed due to a technical issue around the delivery of physical currencies," the CME told customers in a memo seen by Reuters.

CME, which owns the Chicago Mercantile Exchange, the Chicago Board of Trade and the New York Mercantile Exchange, had already postponed the launch of London-based CME Europe Ltd to September 29, for a trade date of September 30, from September 9.

CME plans to offer 30 foreign-exchange as well as options and commodities contracts. Outlining the timeframe for non-currency products for the first time, CME Europe's CEO Robert Ray said it plans to offer options within two months of launching and bring in commodities by the third quarter of 2014.

The exchange will continue to use the Libor interbank lending rate as a basis for its derivatives contracts despite rigging scandals which have undermined trust in the benchmark.

"Nobody can ditch it. Despite the hyperbole, just look at the number of mortgages and loans out there linked to libor," said Ray on the sidelines of a conference in Geneva this week.

Britain has put in place new reforms to tighten how Libor is run and top U.S. regulator CFTC has called for reform to the benchmark at a global level.

"We will just have to work with a different methodology going forward," he said, referring to the reforms.

(Editing by Louise Ireland)