Sri Lankan prime minister, Ranil Wickremesinghe, has been appointed acting president following Gotabaya Rajapaska's leave from the country, Sri Lankan parliamentary speaker announced on Wednesday.

In a televised statement, Mahinda Yapa Abeywardana said president Rajapaksa had appointed prime minister to act as president in his absence in line with the constitution.

Sri Lanka has now declared a state of emergency and a curfew as thousands of citizens continue to demand Ranil's resignation.

The country's military and police fired tear gas at the protesters who have continued to remain undeterred. Rajapaksa's flight out of the country has brought an end to the Rajapaska rule that has been dominant in the island nation for the past two decades.

Sri Lanka continues to face its worst economic crisis, having run out of foreign reserves and declaring bankruptcy while in talks with International Monetary Fund for a bailout.