Ugandan opposition leader Kizza Besigye vowed on Sunday to press on with peaceful demonstrations in his country despite an attack on him by state security agents.

Speaking from a Nairobi hospital where he is being treated for his injuries, Besigye says he is determined to fight for the rights of the Ugandan people.

He said he will continue mobilizing what he describes as "peaceful demonstrations" and walk to work protests calling on the government to act.

"As I have said, what underlies it is the socio-economic crisis in our country.

"The population is largely marginalized and is now protesting their marginalization," Besigye told journalists at a press conference at the hospital.

"I suspect that these activities will definitely continue in one form or another until there is adequate response to the situation," he said.

Besigye was taken to hospital on Friday after Ugandan police smashed the windows of his car and doused him with pepper spray in an incident caught on camera.

The opposition leader told reporters he was aware of the threats on his life, having survived an assassination attempt when he fled the country to South Africa for four years after the 2001 general elections.

"I know that my life is in danger, I have known this for a long time, as you know I had to leave the country for four years after the 2001 elections, I lived in South Africa, I was followed in South Africa by an assassination squad and it was the South African government that intervened and helped me to survive, so there is no doubt the threat that there is to my life," he said.

Asked to comment about statements by Uganda's President Yoweri Museveni in Nairobi on Saturday, to the effect that it was him who ignited violence by spraying police with pepper spray, Besigye denied that this was the case.

"On the fateful day, I obviously did not have any spray, I cannot have any spray.

"I understand that, that fellow who sprayed me, there have been a lot of efforts to track him down and possibly to harm him and his family but we have advised our people that they must make a statement that we have no intention of retribution in our activities," he said.

Doctors treating Besigye said he would have to stay in hospital for four or five days to enable them to monitor his condition.

The opposition leader suffered eye and soft tissue injuries but CT scans revealed that his ribs and spinal cord were not damaged, Dr Timothy Byakika said.