Syria's opposition is to meet in Brussels this weekend in EU-sponsored talks aimed at forging more unity among opponents of President Bashar al-Assad's regime, an EU spokesman said Monday.

The talks will gather the main opposition groups, including the Syrian National Council, the National Coordination Committee for Democratic Change, the Kurdish National Council and the Democratic Forum, the spokesman said.

The meeting is to be led by the Syrians but has financial backing from the European Union "in line with our policy of trying to get the opposition more united," said Michael Mann, spokesman for EU chief diplomat Catherine Ashton.

Syrian intellectuals not directly linked to the political movements will also take part in the talks, which will bring together some 50 participants, he said. An Arab League representative will also be present.

"It should in principle be a low-key event, also to protect the participants," Mann said, adding that the Syrians handled the invitations and programme while the EU's diplomatic service was "just a facilitator and payer."

The event is expected to be opened by Ashton's number two, Pierre Vimont, but no press events are planned.

Syrian government forces on Monday shelled rebel bastions in Homs and Damascus despite opposition pleas for help and a UN warning that such bombardments amounted to crimes against humanity.