UPDATE 1-Japan's Inpex wins stakes in two Malaysian oil prospects

* To explore two deepwater blocks offshore Sabah

* To drill total of 5 wells in two blocks in 2014

* Costs for Block R seen at $123 mln, Block S at $72 mln - Petronas (Adds further details)

TOKYO, Jan 17 (Reuters) - Japanese oil and gas explorer Inpex Corp has won stakes in two oil and gas exploration licences offshore Sabah from Petronas, Malaysia's national oil company.

Petronas selected a four-year work programme Inpex had proposed to explore in deepwater blocks R and S, 180 km west and 120km northwest off the coast of Kota Kinabalu, an Inpex spokesman said.

Separately, Petronas said the minimum financial commitment for the two blocks are $123 million and $72 million respectively.

In Block S Inpex has a 75 percent interest and as the licence operator plans to drill two exploration wells in around 2014. The costs will be shared with Petronas, which has a 25 percent interest.

Block S lies in the Sabah basin where large reserves of oil and gas, such as the Kikeh and the Gumusut-Kakap oil fields, have already been discovered, Inpex said.

In Block R, JX Nippon Oil & Gas Exploration Corp, an upstream subsidiary of JX Holdings, is the operator. Three exploration wells are planned in around 2014, with Inpex and JX each holding a 37.5 percent interest in the licence. Petronas has the remaining 25 percent although interests change if finds prove commercial.

"If and when we find the value of oil and gas in a block is feasible we are obliged to give a certain part of our share of production to Petronas," an Inpex spokesman said. (Reporting by Risa Maeda and Junko Fujita in Tokyo and Niluksi Koswanage in Kuala Lumpur; Editing by Greg Mahlich)