SRI Lankan President Gotabaya Rajapaksa has confirmed he will resign, the prime minister's office has said, after tens of thousands of protesters stormed the official residences of both men.

Sri Lanka is in deep financial crisis and the crowds say they won't leave until both men quit their posts.

The parliament Speaker had earlier said the president would resign on 13 July.

Mr Rajapaksa, whose whereabouts are unknown, has not spoken publicly since his residence was stormed on Saturday.

Sources have told the BBC he is on a navy vessel in Sri Lankan waters. He was moved to safety before protesters entered the presidential palace.

The president has been blamed for the country's economic mismanagement, which has caused dire shortages of food, fuel and medicine for months. His resignation was first announced by the parliament Speaker on Saturday, but many Sri Lankans responded with scepticism to the idea that he would relinquish power.

On Monday, Prime Minister Ranil Wickremesinghe's office said in a statement it had been informed by Mr Rajapaksa that he would step down on Wednesday.

But under Sri Lanka's constitution, his resignation can only formally be accepted when he resigns by letter to the Speaker - which has yet to happen.

Prime Minister Wickremesinghe had earlier also said he would step down from his position. His house was set on fire during Saturday's unrest.

Sri Lanka is an island nation off southern India. It won independence from British rule in 1948. Three ethnic groups - Sinhalese, Tamil and Muslim - make up 99% of the country's 22 million population.

One family of brothers has dominated for years. Mahinda Rajapaksa became a hero among the majority Sinhalese in 2009 when his government defeated Tamil separatist rebels after years of bitter and bloody civil war. His brother Gotabaya, who was defence secretary at the time, is the current president but says he is standing down.