Adds detail on Region 4 controversy, tensions.
Preliminary results from Guyana's 2 March parliamentary elections give the opposition a tentative lead over the ruling coalition, raising the prospect of tougher contract conditions for the oil industry.
A vote-counting controversy in one of Guyana's 10 regions is delaying the final results.
Tensions were rising late today amid accusations by the opposition of fraud in Region 4, which encompasses the capital Georgetown. State-owned media is declaring victory for the ruling coalition, but the elections commission has not issued a final tally.
The outcome is critical to foreign oil companies that are hoping to replicate the success of ExxonMobil, which started production in December at the 8bn bl of oil equivalent Stabroek block offshore.
The opposition People's Progress Party (PPP) has said it would seek to renegotiate production-sharing terms for contracts signed after the watershed ExxonMobil deal. This could impact other contract holders including Chevron and European firms Total, Repsol, Eni and Tullow.
The PPP is currently leading the governing coalition led by the People's National Congress (PNC) by 51,000 votes, according to Guyana's elections commission.
A final election tally could be issued by the commission as early as this afternoon. If the outcome is close, the loser could challenge the result, election observers say.
A PPP victory could delay further offshore development. The party said it would respect the terms concluded with ExxonMobil and its partners - US independent Hess and Chinese state-owned CNOOC unit Nexen, but subsequent contracts would be subject to revision.
ExxonMobil is forecasting that production of light sweet Liza crude from the deepwater Stabroek block will reach 120,000 b/d in March, ramping up to 750,000 b/d by 2025 - the year when Guyana will hold its next parliamentary elections.
