Syria has agreed to allow UN investigators to quiz its officials over the assassination of ex-Lebanese Prime Minister Rafik Hariri.
Rafik Hariri had been at a session of parliament just before the blast
Syrian Deputy Foreign Minister Walid Muallem said the questioning of five officials would be carried out at UN offices in Vienna.
He said Syria had been given "reassurances" on its sovereignty.
The announcement follows weeks of deadlock between the UN investigation and Syria on the issue.
Syria had refused a request by German prosecutor Detlev Mehlis, who is heading the inquiry, to carry out the interviews in Lebanon.
Mr Mehlis was unwilling to accept a Syrian offer to allow questioning either in Syria itself or at the Arab League headquarters in Cairo.
"The [Syrian] leadership has decided to inform Mehlis that it accepts his suggestion, as a compromise, that the venue to listen to the five Syrian officials be the UN headquarters in Vienna," Mr Muallem said.
UN spokeswoman Marie Okabe said Mr Mehlis confirmed the agreement in a telephone call to UN Secretary General Kofi Annan.
One potential sticking point remains, says the BBC's Jon Leyne in neighbouring Jordan.
The UN originally said it wanted to speak to six Syrian officials, but Syria is talking of five officials travelling to Vienna, he says.
KEY UN FINDINGS
Assassins had considerable resources and capabilities
Evidence suggests both Syria and Lebanon were involved
Crime was prepared over several months
Hariri's movements and itineraries were monitored
Highly unlikely Syrian or Lebanese intelligence were not aware of assassination plot
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Mr Muallem told reporters: "Me, I know that the number is five. I don't know where you get the sixth from."
He also said Damascus was not worried that the officials, who are travelling with their lawyers, would be arrested in Vienna.
"Mr Mehlis doesn't have the authority to arrest [them]. He must ask the Lebanese judicial authorities who will then ask Syria," he said.
Mr Muallem would not identify the officials involved, saying it was a matter of the "secrecy of the investigation", or say when the interviews might take place.
Reports from Lebanon suggest the officials include the head of Syrian military intelligence, Assef Shawkat, a brother-in-law of Syrian President Bashar al-Assad.
Syria has repeatedly denied any involvement in the truck bomb explosion in Beirut on 14 February that killed Mr Hariri and 20 others.
But an interim report by Mr Mehlis and his team last month implicated senior Syrian and Lebanese security officials.
The UN Security Council has told Syria to co-operate fully with the investigation or face unspecified action.
Mr Hariri's assassination sparked massive anti-Syrian street protests in Lebanon.
The protests, and growing international pressure including UN Security Council resolution 1559, led to the pull-out of thousands of Syrian troops stationed in Lebanon.