Sultan Qaboos wrested power in 1970 and led Oman's rapid growth and development.
India has suffered an "irreparable loss" of a true friend and well-wisher with the death of Sultan Qaboos bin Said al Said of Oman, External Affairs Minister S Jaishankar said on Tuesday.
One of the longest-serving rulers in the Gulf region and a close friend of New Delhi, Sultan Qaboos died on January 10 at the age of 79.
"Signed the Condolence Book at the Oman embassy expressing our profound sorrow at the sad demise of His Majesty Sultan Qaboos bin Said al Said. India has suffered an irreparable loss of a true friend and well-wisher," Mr Jaishankar said in a tweet.
Sultan Qaboos, who wrested power in 1970 and led Oman's rapid growth and development, was widely respected globally for his vision for the Gulf region.