The day after he became the first foreign leader to visit Cairo since the fall of Hosni Mubarak, Cameron told Kuwait's national assembly that protests sweeping the region were a "precious moment of opportunity".

"For decades, some have argued that stability required highly controlling regimes, and that reform and openness would put that stability at risk," the prime minister said.

But he argued that this was a "false choice", saying: "As recent events have confirmed, denying people their basic rights does not preserve stability, rather the reverse."

He said the most resilient societies possessed key democratic building blocks such as government accountability, freedom to communicate and freedom to learn and work.

"In short, reform not repression is the only way to maintain stability," Cameron said.

In Cairo, Cameron met Field Marshal Hussein Tantawi, Egypt's de facto leader, just 10 days after long-time president Mubarak stood down in the face of an unprecedented popular uprising, the state-run MENA news agency said.

Protests have also erupted in Libya and in his speech Tuesday; Cameron repeated his condemnation of the "appalling" crackdown by security forces.

"Violence is not the answer to people's legitimate aspirations. Using force can not resolve grievances, only multiply them," he said.

The British premier said that reform could also play its part in countering extremism, saying people often turned to violence when they were denied a voice or decent employment.

Cameron stressed that reform was "a key part of the antidote of the extremism that threatens the security of us all."

The prime minister is leading a trade delegation and he agreed with the Kuwaiti government to double bilateral trade and investment, currently worth £2 billion ($3.2 billion, 2.4 billion euros), by 2015.