Egyptian President Mohammed Morsi has warned that continuing unrest is "threatening to paralyse the country".

In a televised speech ahead of the first anniversary of his taking office, Mr Morsi said he had made "mistakes" since becoming president.

Troops have been deployed across Egyptian cities ahead of planned weekend protests demanding his removal.

Ahead of Mr Morsi's speech, deadly clashes broke out in the northern city of Mansoura.

Two people were killed and 170 injured in fighting between supporters and opponents of the government, a health ministry spokesman told the BBC.

Mr Morsi took power on 30 June 2012. His first year in office has been marred by constant political unrest and a sinking economy.

Speaking on Wednesday evening, President Morsi said he had done "his best to evaluate the situation".

"I was right in some cases, and wrong in other cases," he said.

"I have discovered after a year in charge that for the revolution to achieve its goals it needs radical measures.

"Every revolution has enemies and every nation has challenges," he said, adding that he would "address the negatives".

The head of the army earlier warned it would not allow Egypt to slip into "uncontrollable conflict".

BBC