Reasons behind a sudden proposal by Egypt's military authority to swiftly transfer power to civilian rule are far from clear and could be an attempt to undermine the protesters, analysts said.

Field Marshal Hussein Tantawi, who took power when Hosni Mubarak was ousted in February, pledged in a televised address on Tuesday to hold a presidential election by the end of June, a step that would see Egypt's powerful military finally relinquish executive power.

At least on the surface, the announcement was designed to allay the fears of Egyptians who doubted that those crucial elections might not take place until 2013.

Tantawi, who served as Mubarak's defence minister for decades, also insisted that parliamentary elections would begin on Monday, as scheduled, and said he was also ready to transfer power immediately, via a referendum, "should the people wish it."

But political analyst Hassan Nafaa called the proposals by Egypt's interim head of state "ambiguous," and said the army "still needed to demonstrate that the transfer of power would take place in an acceptable way."

Without a new constitution, the powers of the future president remained in question, he said, with the risk that they could be limited for the benefit of the army.

During the latest wave of protests, many have called for the withdrawal of a government document proposing supra constitutional principles, which could see the military maintain some control over the country's affairs and keep its budget from public scrutiny.

Analysts say Tantawi's suggestion of a referendum to decide on the eventual transfer of power could be used against protesters demanding the rapid departure of the military, which as a whole remains popular in Egypt, despite the criticism of its leaders.

"It's very difficult to say that Tahrir is representative of the entire country. There are a lot of people in Tahrir. But obviously a lot more people are not protesting," Egyptian analyst and blogger Issander El-Amrani told AFP.

But he acknowledged that the military also faces a dilemma that existed under Mubarak.

"It was the same during the uprising; there was a silent majority that didn't feel like joining, they were perhaps against it. But at that end of the day it was Tahrir that decided the course of events," Amrani said.

"The military faces the same problem Mubarak did. They can't crush Tahrir, for domestic reasons and for international reasons. And the result would be a bloodbath," he added.

Sticking to the schedule of planned parliamentary elections, due to begin on Monday and last several months, might not help clarify the situation, Hassan Nafaa said.

"It isn't necessary to have legislative elections now, when the environment is not favourable and their security is not there."

The Muslim Brotherhood, although highly critical of the military rulers, opposes any postponement of the legislative vote, feeling it is in a strong position.

But some argue that cynical political calculations by the country's interim leaders and the Brotherhood are in fact driving many of the demonstrators.

"I think there is a message from the youth that they are fed up with... political bargaining," said Nabil Abdel Fatah, analyst at the Al-Ahram Centre for Political and Strategic Studies.

"This is a development that neither the authorities nor the political parties saw coming," he added, referring to the mass demonstrations that have swept Egypt in recent days, and which bore similarities to the ones that toppled Mubarak nine months ago.

In this context, the political concessions by the military rulers may not be enough.

Many liberal, secularist and left-wing groups are now demanding a complete review of the political system, with a presidential election before the parliamentary vote, and the formation of a "national salvation" government as swiftly as possible.