The federal environment ministry wrote back in May this year asking Reliance to meet certain conditions in order to secure a green light for the projects, the documents show.
It was not immediately clear if there had been further communications between Reliance and the environment ministry. The documents did not reference a potential start up date.
Reliance did not respond to an email seeking comments.
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"It makes perfect sense to go aggressive in their core business of refining," said Jagannadham Thunuguntla, head of research and chief strategist at SMC Global Securities Ltd.
"The company's balance sheet has enough firepower to finance refining and other businesses like telecom and retail."
The company had cash and equivalents of $13.6 billion as of end-June.
Expanding Jamnagar would strengthen the role of Gujarat - led by Prime Minister Narendra Modi before his landslide general election victory in May - as a global supplier of fuels in addition to meeting rising local demand.
India's diesel and petrol output may lag demand by about 50 million tonnes by 2025, according to a government panel report, as the world's fourth largest oil consumer aims to powers its economic expansion through a renewed focus on manufacturing. Imports were around 320,000 tonnes in the last fiscal year.
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Reliance also wants to improve the ability of the Jamnagar complex to produce more value-added 'light' products by processing heavier grades than competitors in China and the Middle East.
"Recently the competitiveness of Jamnagar refining hub is gradually declining due to fast changing global scenario of product demand and stringent fuel quality," said the proposal, obtained under India's Right to Information Act.
While Reliance has not said by when the proposed projects will be in place, analysts and industry sources said the new refinery is expected to be built by the end of this decade.