Syrian President Bashar al-Assad has condemned the "abominable" massacre of more than 100 people in Houla, saying even monsters could not carry out such acts.

In a speech to parliament he promised the 15-month-old crisis would end soon if Syrians pulled together.

Mr Assad repeated many of his earlier pledges to maintain a crackdown on opponents he describes as terrorists implementing a foreign conspiracy.

He also offered dialogue with those opposition figures who have avoided armed conflict or outside backing.

He made his comments a day after international envoy Kofi Annan said the spectre of all-out civil war was growing daily in Syria and the world needed to see actions, not words, from Assad.

In his hour-long address, Mr Assad offered no specific response to Mr Annan's plea for bold steps to end the conflict.

Thousands of people have been killed in a crackdown on protests against Assad, which erupted in March last year and have become increasingly militarised, destabilising neighbouring Lebanon and raising fears of regional turmoil.

"This crisis is not an internal crisis. It is an external war carried out by internal elements," Mr Assad said, looking relaxed as he spoke to parliamentarians. "If we work together, I confirm that the end to this situation is near."

Western powers have accused Syrian armed forces and pro-Assad militia of responsibility for the 25 May Houla killing, a charge Damascus has denied.

"What happened in Houla...and what we described as ugly and abominable massacres, or true monstrosities - even monsters do not perpetrate what we have seen," Mr Assad said.

He said his country was facing a war waged from outside and that terrorism was escalating despite political steps including last month's election for parliament, whose new members he was addressing.

Authorities will maintain a crackdown against the armed opposition but were still ready for dialogue with political opponents, he added.

Abdelbaset Sida of the opposition Syrian National Council dismissed the speech as more rhetoric.

Mr Annan, the joint United Nations and Arab League envoy for Syria, told an Arab League meeting in Qatar yesterday that Mr Assad must make "bold and visible" steps immediately to change his military stance and honour his commitment to cease all violence.

He criticised Mr Assad for failing to comply with a peace plan to end the conflict and said his forces were carrying out atrocities, arbitrary arrests and other abuses.

The United Nations says Syrian forces have killed more than 9,000 people in a crackdown on protests against Assad. Syria blames the violence on foreign-backed Islamist militants it says have killed more than 2,600 soldiers and security force members.

Reports from Syria cannot be independently verified due to state restrictions on foreign media.