The President of Cuba has thanked Pope Francis for helping negotiate the recent rapprochement between Cuba and the US.

Raul Castro joked that he would "resume praying and turn to the Church again" if the Pope continued to help his country.

The Communist leader dropped into the Vatican for an audience with Pope Francis on his way home from Russia's World War II Victory Day parade in Moscow.

The 78-year-old Pope has promised to visit Cuba in September.