Urals in January was around $49.48 a barrel - in line with the figure used for tax purposes - down 42% from a year earlier and well below the $70.1 per barrel Moscow has used in its 2023 budget planning.
Moscow relies on oil and gas income to fund its budget, but has been forced to start selling foreign currency reserves to cover a deficit that stretched to 1.76 trillion roubles ($24.8 billion) in January to cover the cost of the military operation in Ukraine.
Urals crude differentials to dated Brent slipped to minus $30 a barrel in December from minus $24 in November, remaining sharply below the single-digit discounts seen prior to 2022.
Another proposal was to set the differential for tax purposes at dated Brent minus $25 a barrel with a gradual narrowing to minus $20 a barrel, the sources added. Russia's oil and gas revenue last year totalled around 11.6 trillion roubles ($165 billion). (Editing by Hugh Lawson; Editing by Kirsten Donovan)