Just hours after Crown Prince Sidi Mohammed announced that his father had died of a heart attack, he was sworn-in as Mohammed VI and commander of the faithful at a ceremony in the royal palace in the capital, Rabat.

As cabinet ministers lined up to pay homage to King Mohammed by kissing his hand, hundreds of ordinary people gathered at the palace gates to express their allegiance. Many were weeping.

The new king has already appealed to Moroccans to remain loyal to their monarchy - one of the oldest in the world.

A 40-day period of national mourning has been declared across the country.

Police ordered the shutters to be closed on shops and buildings in Rabat, leading to reports of panic buying.

Graham Satchell reports: "He's likely to be best remembered as a man who worked tirelessly for peace in the Middle East"

King Hassan - who was credited with playing a key role in the Middle East peace process - died while being treated in the Ibn Sina hospital for pneumonia. He was 70.

The new king appeared on television to announce the death.

"My father, His Majesty King Hassan, may God bless his soul, died of a heart attack at 1630 (GMT) due to a complication that could not be treated," he said.

In a brief message to the Moroccan people, King Mohammed, with his younger brother Prince Moulay Rachid at his side, called for "calm and patience".

The BBC's Nick Pelham: "Sound of Koran reverberated"

King Hassan's funeral will be held on Sunday at the mosque which bears his name. He will be buried next to his father, King Mohammed V. Services will begin with a midday prayer.

Foreign leaders including United States President Bill Clinton and his wife Hillary are expected to attend.

PLO leader Yasser Arafat and Israeli Prime Minister Ehud Barak have reportedly postponed a key meeting scheduled for Saturday so that they too can attend the funeral.

Palestinian officials are quoted as saying the confidence-building meeting will now take place on Tuesday.

Smooth succession

Mourners took to Casablanca's streets on news of the king's death

The enthronement of Mohammed VI, less than three hours after the announcement of the death of his father, emphasises the desire in Morocco to ensure a smooth and swift succession.

At the time of his death, King Hassan was the Arab world's longest-reigning monarch. He had been on the throne since 1961.

He had appeared tired after he returned from a recent visit to France.

He was taken to hospital four years ago in the United States suffering from pneumonia, and had respiratory complaints ever since.

Human rights critics

King Hassan was a leading political figure in North Africa and a strong Arab nationalist.

But his human rights record was heavily criticised internationally. At home, he often faced criticism for his repressive measures against dissidents.

The BBC's Nick Pelham in Rabat says Morocco remains a deeply unequal society and King Hassan's legacy is a state which in terms of development has changed only in part since independence from France.