Spain's King Juan Carlos abdicates.

King who helped smooth country's transition to democracy in the 1970s after Franco era, to be succeeded by son.

Juan Carlos, king for almost 40 years, has seen his popularity dip of late following royal scandals

Spain's King Juan Carlos is abdicating after almost 40 years on the throne and his son Prince Felipe de Borbon will succeed him, the Spanish prime minister has announced. Juan Carlos, whose health is failing and has had a number of hip operations in recent years, is stepping down for personal reasons, Mariano Rajoy said on Monday. "His majesty, King Juan Carlos, has just communicated to me his will to give up the throne," Rajoy said. "I found the king convinced that this is the best moment to change the head  of state in all normality and for the transition of the crown to the Prince of  Asturias (Prince Felipe)," he said. Prince Felipe, a former Olympic yachtsman, has been relatively unscathed by the scandals that battered others in the family. Juan Carlos's daughter, Princess Cristina, and her husband, Inaki Urdangarin, are under investigation in a corruption case. Princess Cristina is suspected of tax-fraud and money-laundering. Once popular Juan Carlos, 76, who helped smooth Spain's transition to democracy in the 1970s after the Francisco Franco dictatorship, has lost public support in recent years due to corruption scandals and gaffes. His popularity also dipped following royal scandals, including an elephant-shooting trip he took in the middle of Spain's financial crisis that tarnished the monarch's image. The Botswana trip, which came to light after he broke his right hip and was flown home for surgery, undermined the king's earlier declarations that he lost  sleep thinking about unemployed young people. Amid signs that public opinion for the monarchy was slipping in the economic crisis, the king apologised publicly for the trip as he emerged from hospital on crutches. In a poll published in January 2014 by El Mundo, the number of people with a high or very high opinion of the king fell nine percentage points over 2013 to 41 percent. The number of people wanting him to abdicate in favour of his son Prince Felipe, 46, surged by 17 percentage points to 62 percent, according to the survey by pollster Sigma Dos.