The change follows the Abu Dhabi National Oil Company (ADNOC) saying on Monday that it plans to build a new international exchange for its flagship Murban crude which will start pricing its oil on a forward pricing basis.

QP currently prices two of its grades - Qatar Land and Qatar Marine - on a retroactive basis but will move this to forward pricing, a more popular approach used by other Middle East crude exporters such as Saudi Arabia that better matches the trading cycle of crude, the sources said.

For example, QP announced OSPs for October earlier this month while Saudi Arabia has set its prices for December.

Middle East sour crude grades are typically traded two months forward in the Asia market, meaning that January-loading crude cargoes are currently being traded in the November spot market.

By moving prices for Qatari grades forward, it allows traders to compare prices among Middle East supplies, traders said.

QP aims to implement the pricing formula change in the first quarter and will set the prices at differentials to the monthly average of Platts Oman and Dubai quotes, the sources said.

One of the sources said QP will set dummy prices for a few months to obtain feedback from customers before the change.

The producer has released its first set of dummy prices for December, he said.

The company did not immediately respond to a request for comment.

As part of its efforts to determine market value for its crude, QP offered one 500,000-barrel cargo of January-loading Qatar Marine crude in a rare tender, traders said. Bids can be priced based on Dubai quotes.

By Shu Zhang and Florence Tan