* Output steady as Rosneft's Vankor pumps ahead of plan
* Saudi output contributes to overall OPEC increase
* Daily gas output falls as cold eases (Adds Rosneft field output, background on production incentives, Saudi competition)
MOSCOW, April 2 (Reuters) - Russian oil output stood at 10.36 million barrels per day in March, unchanged from a post-Soviet monthly high in February, Energy Ministry data showed on Monday.
Measured in tonnes, crude production in Russia, the world's top producer, was 43.8 million tonnes last month, the ministry said.
Russia is broadly expected to increase output by 1 percent this year from last year's average of 10.27 million barrels per day if it can control declines at old West Siberian fields and sustain output growth from new fields in more remote provinces.
Rosneft, whose new Arctic field, Vankor, is expected to be a key driver of those modest gains this year, said last week that the field, which is gradually ramping up output to peak production of 500,000 barrels per day next year, was about 18,000 barrels ahead of plan for the first quarter.
A new export duty regime aimed at encouraging crude oil production and exports has yielded modest results, and producers are keen to capture gains in oil prices, which broke $128 per barrel this year, largely due to sanctions against Iran.
Russian producers are capable of marginal production increases to capture high prices, but, unlike Saudi Arabia, its rival for the title of top world oil producer, has little capacity cushion to help ease supply shocks.
The kingdom's oil output edged up to 9.9 million barrels per day last month, contributing to an overall increase in output by the Organisation of the Petroleum Exporting Countries (OPEC) which neutralised a fall in Iranian output.
Daily gas production declined slightly after a bump in production to help meet elevated demand during a cold snap in early February. It totalled 62.19 billion cubic metres in March, or 2.00 billion cubic metres per day.
Russia's daily gas production was 2.07 billion cubic metres in February. (Reporting by Olesya Astakhova and Katya Golubkova; Writing by Melissa Akin; Editing by Erica Billingham)