BANGKOK( Reuters)-Thailand's cabinet has backed a plan to buy four fighter jets starting in the next fiscal year, an air force spokesman said on Wednesday, with a budget of 13.8 billion baht($ 413.67 million) set aside for the procurement. The approval follows a recent expression of interest by the air force chief, Air Chief Marshal Napadej Dhupatemiya, in procuring eight F-35 fighter jets from Lockheed Martin Corp of the United States. The cabinet has agreed the budget for a four-year period st