BAKU (Reuters) - Oil output from BP (>> BP plc)-led oilfields in Azerbaijan in 2014 was down slightly from a year earlier, BP-Azerbaijan said on Thursday, driving a fall in the country's total oil production.

Falling oil production at the Azeri-Chirag-Guneshli (ACG) oilfields, which account for most of Azerbaijan's output, has raised concern in the former Soviet republic.

Oil output at the ACG declined to 31.5 million tonnes in 2014 from 32.2 million tonnes in 2013.

BP said the consortium spent approximately $1 billion in operating expenditure and $2.3 billion in capital expenditure on ACG activities in 2014. In 2013, it spent about $772 million in operating expenditure and $2.8 billion in capex.

BP said more than 298.5 million barrels of oil had been exported from the Sangachal terminal in 2014.

Azerbaijan's total crude oil and condensate production fell to 41.9 million tonnes last year from 43.1 million tonnes in 2013, a source at the State Statistics Committee said in January.

The British oil major and its partner, Azeri state energy firm SOCAR, tried to calm worries about declines in oil production in 2013, saying production had stabilised. Total oil output rose in 2013 for the first time since 2011.

BP started maintenance work at the Central Azeri and West Azeri platforms on Oct. 31, halting operations for a month, in a move that could further reduce oil production in the country. Production resumed on Nov. 27.

Natural gas output from the Shah Deniz offshore fields in Azerbaijan rose to 9.9 billion cubic metres (bcm) last year from 9.8 bcm in 2013.

Shah Deniz is developed by a group of investors including BP, Statoil (>> Statoil ASA), and SOCAR. It is estimated to contain 1.2-1.5 trillion cubic metres (tcm) of gas.

Shah Deniz I has been pumping gas since 2006, while gas from its second stage is expected to reach Europe by 2019-20.

Overall gas production in Azerbaijan rose to 25.2 bcm in January-September 2014, from 24.0 bcm in the same period last year. There is no data for total gas production in Azerbaijan in 2014 so far.

BP said the Shah Deniz consortium had spent around $0.4 billion in operating expenditure and $3.9 billion in capital expenditure last year.

(Reporting by Margarita Antidze, editing by William Hardy)

By Margarita Antidze

Stocks treated in this article : Statoil ASA, BP plc