Correspondents say that although the official announcement does not say it in so many words, for practical purposes this marks the declaration of martial law in Pakistan.

The declaration of a state of emergency came in the early hours of Friday morning. At the same time, General Pervez Musharraf assumed the position of the country's chief executive.

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Within minutes of the announcement, fighter planes were heard flying over Islamabad.

But when morning broke there was little sign of any extra troop presence and life appeared to be going on as normal.

Later on Friday, a military spokesman said General Musharraf would make an address to the nation either late that night or on Saturday morning.

The spokesman, Brigadier Rashid Qureshi, said the speech would deal with the issues of stability, sincerity, transparency, accountability, good governance and consistency of policies.

The general would also talk about his plans for the future.

In one of their first acts, the military have frozen the accounts of Mr Sharif, other senior politicians, parliamentarians, political advisers and their spouses.

"The central bank has decided that temporarily all transactions in these accounts have been stopped until further order," one banking source was quoted as saying.

Constitution suspended

In his official announcement, General Musharraf said the National Assembly and all the provincial assemblies have been suspended, and the provincial governments and governors have been dismissed.

The constitution has been suspended and the Supreme Court has been banned from challenging the authority of General Musharraf.

The Provisional Constitution Order No.1 also makes it clear that President Rafiq Tarar is now subordinate to the general. The president is required to act on, and in accordance with, the advice of the chief executive.

General Musharraf's actions came despite repeated calls from the international community for a return to civilian rule.

The UK, which had expressed outrage at the coup, described the declaration of a state of emergency as "deeply worrying".

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However the White House gave a cautious reaction to the news, and said it was still assessing what the outcome would be.

Earlier in the day President Clinton had renewed his calls for the country to be restored to civilian rule as soon as possible.

No alternative

Ever since the military takeover on Tuesday, the army had maintained a stony silence about its plans for the future governance of Pakistan.

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The BBC's Owen Bennett-Jones in Islamabad says that as martial law was not declared immediately after the coup, it appears likely that Friday's decision was not the preferred option of General Musharraf.

However in the end it appears it was impossible for General Musharraf to come up with an alternative formula.

It seems the general feared that without imposing martial law he could have been accused of behaving illegally by overthrowing the democratic government of Mr Sharif, our correspondent says.

General Musharraf: Seized control of Pakistan

The chief-of-staff had spent Thursday ensconced in talks with senior army commanders and political figures, including President Tarar.

Troops sealed off the parliament building earlier on Thursday, throwing out office workers and a few legislators.

Before the coup that deposed the government of Mr Sharif, parliament had been due to meet on Friday.

Members of Mr Sharif's party had been reportedly planning to try to enter parliament to hold the scheduled session, in defiance of the army closure.

'Plot to kill' Musharraf

Pakistan's military leaders said on Thursday that they had staged the coup in order to prevent an attempt to assassinate General Musharraf.

A military spokesman said the alleged conspiracy became apparent while the general was returning to Pakistan from a visit to Sri Lanka and as Mr Sharif was trying to sack him.

Brigadier Rashid Qureshi said the plot involved blocking the runway at Karachi airport and destroying the general's aircraft - a Pakistan International Airlines flight carrying more than 238 passengers, which was rapidly running out of fuel.

He said the military became aware of what was happening and army units rushed to the airport to clear the runway so that the general's plane could land.

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