The extension of Oman's main airport in Muscat will be delayed by two years and may cost the state up to an extra $500 million after runway excavations hit seawater, a government official said on Wednesday.   

'The Muscat airport extension will now be completed in 2014, not in 2012 as expected due to soft ground which contractors come across in some places,' the official, who asked not to be named, told Reuters.

He said it would cost the government up to $500 million to pay for reinforcements to fill affected ground in places where civil work excavations hit seawater.

Last year, Oman awarded a joint venture of Turkey's TAV Construction and Athens-based Consolidated Contractors Co (CCC) a $1.17 billion contract for civil works for the Muscat airport.   

This is the second snag to hit the seaside Muscat airport after the cyclone Gonu that hit Oman in 2007 forced a master plan modification.   

Oman has yet to award the construction contract for the terminal building at Muscat airport after four international firms were shortlisted in 2009.

The airport currently handles about 4 million passengers a year and will be able to handle 12 million passengers after the extension. Oman is also building new airports at Duqm, Ras Al Hadd, Musandam and Sohar. - Reuters