Oman is celebrating its 40th National Day on Thursday. The occasion commemorates the beginning of Sultan Qaboos bin Said's leadership on this day in 1970 and the start of the Renaissance of Oman. Marking the 40th National Day, Sultan Qaboos presides over the military parade in which units from the Royal Army of Oman, Royal Air Force of Oman, Royal Navy of Oman, Royal Guard of Oman and Royal Oman Police take part. Sultan Qaboos bin Said has received congratulatory messages from leaders of various Arab and friendly countries including Indian President Mrs. Pratibha Devi Singh Patil on the occasion of National Day. India and Oman have close political, economic and cultural relations. There are around 5 lakh 50 thousand Indians living in Oman, constituting the largest expatriate community in the country. AIR correspondent reports, India-Oman relations have been marked by regular high-level contacts, which have helped to foster close understanding and a shared vision to develop a partnership in the areas of politics, economics and culture.