Student demonstrators surrounded the Sri Lankan Prime Minister's Residence here on Sunday, as the anti-government Galle Face protests reached its 16th day and the clamour for the President and Prime Minister to resign grew louder, PTI reported.

Thousands of Inter University Students' Federation (IUSF) supporters were seen sloganeering outside the Prime Minister's Residence in Wijerama Mawatha. Dozens were demonstrating from the parapet and boundary walls of the official residence - in images similar to that of a seize.

The agitators demanded both President Gotabaya Rajapaksa and Mahinda Rajapaksa resign. The slogans ranged from soft jibes to strait taunts. Some defaced the boundary walls with graffiti reading "Go home, Rajapaksa!"

Thousands of demonstrators have hit the streets since April 9, as the government ran out of money for vital imports; prices of essential commodities have skyrocketed and there are acute shortages in fuel, medicines and electricity supply.

The protests seemed to take a more belligerent turn on Sunday, a day after Prime Minister Mahinda dismissed calls for an interim government, according to PTI.

A defiant Mahinda on Saturday said: "What use of interim governments when people with varying policies can't see eye to eye? There has to be accord which is not possible. If there is a need for an interim government it should happen only under my leadership."

Mahinda reiterated that a unity government could be formed but only under his leadership.

Last week, the ruling dispensation reached out to the Opposition parties and protesters for talks, but all efforts were rebuffed as the agitators said they want the government to resign.

Meanwhile, the police over the weekend warned protesters from entering certain roads in Colombo, saying they have court orders. The students say no court sanctions have been made, PTI reported.