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LONDON (MarketWatch) -- Citibank has stopped making obligatory precious metals markets for other banks but is continuing its precious metals business for customers, a spokesman for Citibank, a subsidiary of Citigroup Inc. (C: C 24.27, -0.84, -3.3%) , said Monday.

"We continue to make aggressive markets in precious metals for our customers, and when it suits us we will also make markets for our competitors. We are no longer going to be part of the obligatory market-making scheme for our competitors," Citibank spokesman Jeffrey French told Dow Jones Newswires.

Market makers are price makers and are obliged to display bid and offer prices. Most traders are so-called price takers - they get to pick and choose when to get in and get out of the market. Being a market maker doesn't provide protection in terms of orders and can therefore be expensive at times, traders said.

Citibank said it stopped making the obligatory spot, forwards and options markets for other banks since late autumn. Citibank services the precious metals markets 24 hours a day from its London and Singapore offices, the bank said.

The bank said the changes were made due to balance sheet constraints and not related to subprime mortgage market losses and the changes haven't resulted in job losses. A message via the Reuters dealer system was sent around out of Singapore earlier Monday to brokers.

Even though the bank said the changes weren't a result of the subprime, Citigroup Inc. has been one of the banks hit heavily by the subprime mortgage market losses. It reported its first quarterly loss since 1998 in January. The company swung to a fourth-quarter loss of $9.83 billion. Continued woes in the subprime-mortgage market caused the bank to book pre-tax write-downs and credit costs of about $18.1 billion.

The bank posted another loss in the first quarter of 2008 and announced job cuts would continue in the second quarter of this year. Citigroup plans to cut 9,000 more jobs during the second quarter, which comes on top of the 4,200 job cuts that Citi made in the last quarter.

Friday the bank reported a first-quarter loss of $5.1 billion, stemming from asset write-downs of nearly $14 billion as well as mounting losses from consumer products such as credit-card and home-equity loans.

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