Oman has extended until August 31 a deadline for international firms, including French Vinci and Indian Larsen & Toubro, to bid for the construction of a new terminal at Muscat's main airport, the Gulf Daily News has reported. The tender, which contractors say is worth about $1.4bn, has already been pushed back twice this year. 'Bidders need more time to prepare for the new changes,' an Oman tender board official has said.