Student activists held strikes in Egypt on Saturday to mark a year since they toppled long-time Egyptian dictator Hosni Mubarak, leaving an increasingly unpopular and defiant military in charge.

The call for strikes in universities and work places came after a series of protests pressuring the military to transfer power immediately to civilians, rather than wait for presidential elections later this year, international media note.

Students from Egypt's main universities began protests at 8 am GMT, and others were expected to head to the iconic Tahrir Square - epicenter of the protests that toppled Mubarak.

The call for strikes have so far seen only a modest response, but activists plan to hold further actions after Saturday's day-long strike.

State television said transport workers will not be going on strike and the state-owned daily Al-Ahram headlined: "The people reject civil disobedience."

The military, headed by Mubarak's long-time defence minister Field Marshal Hussein Tantawi, has said it will deploy additional troops across the country in response to the call for a day of disobedience.

On Friday, thousands of protesters snaked through Cairo's streets to bypass military cordons and reach the defence ministry, chanting: "Down with military rule!"

In a statement read out on state television late on Friday, the Supreme Council of the Armed Forces (SCAF) said it would not bow to threats or plots against the state.

"We will never yield to threats, and we will never give in to pressure," the SCAF said. "We tell you quite frankly that our dear Egypt faces plans aimed at striking at the heart of our revolution.

"We are facing plots against the nation aiming to undermine the institutions of the Egyptian state, and to topple the state itself so that chaos reigns."

The military, which has bloodily crushed several protests in the past year, has played on the widespread suspicion in Egypt of foreign conspiracies.

Secular youth groups that spearheaded the revolt against Mubarak also took part in Saturday's strike. In a joint statement on Friday, the groups urged Egyptians "to support these strikes in order to end the unjust rule and build a nation in which justice, freedom and dignity prevail."

The call for strikes and protests has divided the country's political forces, with the Muslim Brotherhood - the big winner in parliamentary elections - coming out against it.

The military issued a similar warning saying on Friday that the nation was at "the most dangerous turning point on our road to liberty, democracy and social justice."

Young activists who spearheaded the revolt against Mubarak believe the generals will try to exercise power through a pliant civilian government after presidential elections set to take place before the end of June.

The activists say the military should hand power to parliament, elected over three rounds in November and December, or to a civilian council ahead of presidential elections. The SCAF statement said it was determined to transfer power to an elected civilian body.

"We have kept the first promise and returned legislative power to the people's assembly," it said. "Presidential power will pass to the president of the republic after the election ending the period of transition, and your faithful army will revert to its original role."