RIYADH -- Saudi Arabia has raised to 15 percent the rate of return from downstream facilities in three mega gas projects in a bid to break a stalemate with foreign companies, a newspaper quoted an oil executive as saying saturday.

Al-Madina said Foreign Minister Prince Saud al-Faisal, who heads the kingdom's negotiating team, made the offer early September in a letter to the lead firms Exxonmobil and Royal Dutch/Shell.

The Oil Executive Reportedly said the Saudis have offered a "guaranteed rate of return of between 14.5 to 15.5 percent" from the power generation, water desalination and petrochemical facilities associated with the projects.

"The Saudis are expecting to get a response from the companies within one month of receiving the offer," said the executive who added that Prince Saud made a "take-it-or-leave-it" final offer.

Foreign companies have been demanding a rate of return of 18 to 20 percent as against the Saudi initial offer of 10 to 12 percent.

Saudi Arabia has also agreed to increase the quantities of gas available for the foreign firms to make the investment viable, the executive said, AFP reported.