DAMASCUS, Syria (AP) _ Amid a frenzied national outpouring of grief, Syria's leadership lined up behind late President Hafez Assad's son as the choice to succeed him, with the parliament speaker on Monday declaring Bashar Assad as capable as his father.

But in an almost Shakespearean twist, a new threat emerged from within the Assad family. Rifaat Assad, younger brother of the late president who has been in exile in Europe since attempting to seize power in 1983, made his own claim to the presidency just one day before Hafez Assad was to be buried.

In the first open challenge to what has otherwise been a smooth transition, Rifaat Assad promised a ``corrective movement'' in Syria _ a term used to refer to Hafez Assad's coup in 1970. The statement to the Syrian people was read Monday night by an announcer on Arab News Network, a London-based satellite television station owned by Rifaat's son Sawmar.

Earlier Monday, Rifaat said through a spokesman that he planned to return to Damascus at the ``appropriate time'' to contest his nephew's leadership.

``He (Rifaat) represents legitimacy in Syria,'' Rifaat Assad's spokesman Al-Hareth Al-Khair said, adding that ``the people and the army ... are with him.''

Al-Khair appeared to be exaggerating the extent of Rifaat's following in Syria. He enjoyed considerable popularity at the time of his work alongside his elder brother, but his long years in exile and the removal of his supporters in the army and the ruling Baath party renders him a spent political force.

The army has already publicly pledged its backing for Bashar Assad.

Though Syria adopted a republican system after independence from France in 1946, the hereditary succession and familial challenge to the presidency was reminiscent of Shakespeare's dramas about European royalty. But the speaker of the People's Assembly, Abdul-Qader Qadoura, also a member of the party's national leadership, brushed aside talk of a ``royal republic,'' saying Syria was governed by ``institutions.''

In the streets of Syria, the people declared their support for the late president's son, chanting his name and waving his portrait alongside those of his father in mourning marches that erupted in cities and towns throughout this country of 17 million people.

Readings of verses from the Koran, Islam's holy book, echoed from mosque speakers throughout the night. In the early hours Tuesday some Syrians, dressed in black, walked silently along the route the funeral cortege would take later in the day when Hafez Assad's body was to be taken from Damascus to his hometown of Qardaha, 200 miles north.

With shops closed in a show of respect, street hawkers did a brisk business selling portraits of Assad, Bashar and his elder brother Basil, Assad's first choice for a successor who died in a road accident in 1994. Black cloth was also sold by the yard to hang on buildings and fly from car antennas.

Hundreds of thousands of banners and poster-size portraits of Assad and his two sons were plastered on buildings, cars, motorcycles and even the bare chests of male Syrians taking part in the mourning marches, most of which were accompanied by drummers. A few mourners even cut themselves to express their sorrow, in keeping with Shiite Muslim tradition.

The frenzy of mourning, though officially orchestrated like all other mass displays in Syria, carried an element of genuine grief. Assad was the only leader many Syrians had ever known, and despite _ or perhaps because of _ his iron-fisted rule, he instilled in ordinary Syrians a sense of security and national pride.

In the face of such an outpouring, Rifaat Assad's spokesman Al-Khair stressed that the challenger will work through peaceful means. Rifaat, he said, ``stresses peaceful action and refraining from spilling blood and does not want Syria to drown in blood. But he believes that legitimacy will prevail in a rightful way.''

Rifaat Assad, 63, who has a political science doctorate from the former Soviet Union _ his thesis was on class struggle in Syria _ was once vice president to his brother.

Bashar Assad has in the three days since his father's death received the crucial support of the armed forces' top brass, been promoted from colonel to general and been nominated to the office of president by the leadership of the Baath party. It was the tribute his father, who had groomed him for succession, might have wanted more than any other.

Qadoura heaped lavish praise for Bashar Assad's abilities Monday.

``The mission of defending and loving the nation is not linked to a man's age,'' he told a news conference. ``We believe that every citizen in Syria who is capable of giving should be allowed to give regardless of his age.''

``The challenges are the same, the people are the same and the baton has been handed over to someone who came from this party and this people. Therefore he is capable of dealing with the challenges,'' said Qadoura.

As Syrians took to the streets for the third straight day chanting ``Assad is in heaven!'' and ``Bashar, Bashar, we sacrifice our blood and lives for you!'' world leaders and dignitaries began to assemble in the capital, Damascus, for Tuesday's funeral. Late into the evening, state television showed them arriving at the Damascus airport.

Among the first to arrive were Sudanese President Omar El Bashir and former Pakistani Prime Minister Benazir Bhutto. Most dignitaries, including French President Jacques Chirac, U.S. Secretary of State Madeleine Albright and British Foreign Secretary Robin Cook, were due to fly in early Tuesday.

The United States listed Assad's Syria as a sponsor of terrorism, criticized its human rights record and grew frustrated at delays in the Israeli-Syrian peace talks it tried to mediate.

But Monday, as she prepared to head to Syria, Albright said: ``I think that it's totally appropriate that we pay our respects to a historic figure and that we express our condolences to the people of Syria.''