India's Bharat Petroleum has turned to Saudi Arabia, the world's top oil exporter, for higher supplies in 2012/13, fearing global sanctions may jeopardise trade with Iran, industry sources said on Wednesday.

Saudi Arabia is the biggest oil supplier to India, the world's fourth-biggest oil consumer, and is the only oil producer with significant spare capacity to replace any fall in supply from its regional rival Iran.

Iran has offered extra oil supplies to Asian buyers as it seeks to retain market share in the face of western sanctions aimed at stopping Tehran using its nuclear programme to develop weapons. Iran denies it has such an ambition.

While India has said it will not implement the sanctions, it, along with China and Japan, are planning cuts of at least 10 percent in Iranian crude imports as US measures make it difficult for the top Asian buyers to keep doing business with the Opec producer.

BPCL, India's second-biggest state refiner, is the third Indian company after Hindustan Petroleum and Mangalore Refinery and Petrochemicals to seek higher volumes under term deals from Saudi Arabia.

It is seeking a 27 percent increase to 152,000 barrels per day (bpd) in its oil deal with Saudi Arabia for 2012/13 from the previous year, one of the sources said.

BPCL is seeking higher volumes for its plants at Mumbai and Kochi, this source said. The company plans to continue buying 70,000 bpd for its Bina refinery in central India operated by Bharat Refinery Ltd (BORL), a joint venture of Bharat Petroleum and Oman Oil Co.

Another source confirmed plans to increase the size of the annual crude import deal with Saudi Arabia, and added that the refiner planned to reduce the Iranian deal size by about 50 percent to 10,000 bpd in 2012/13.

One of the sources said there was a government directive to reduce crude imports from Iran by 15 percent. He declined to say whether the cut by BPCL would be deeper than 15 percent.

All the sources have direct knowledge of the matter but asked not to be identified as they were not authorised to speak to the media. A BPCL spokesman declined to comment.  - Reuters