BEIRUT – As Syrian forces stepped up their assault Wednesday on rebellious cities, President Bashar Assad ordered a referendum on a new constitution that would create a multiparty system in a country that has been ruled by his autocratic family dynasty for 40 years.

Such a change would have been unheard of a year ago, and Assad’s regime is touting the new constitution as the centerpiece of reforms aimed at calming Syria’s upheaval. But after 11 months of bloodshed, with well over 5,000 dead in the regime’s crackdown on protesters and rebels, Assad’s opponents say the referendum and reforms are not enough and that the country’s strongman must go.

“The people in the street today have demands, and one of these demands is the departure of this regime,” said Khalaf Dahowd, a member of the National Coordination Body for Democratic Change in Syria, an umbrella for several opposition groups in Syria and in exile.

Assad’s call for a referendum, set for Feb. 26, also raises the question of how a nationwide vote could be held when many areas see daily battles between Syrian troops and rebel soldiers.

Regime forces Wednesday battered rebellious neighborhoods in the central city of Homs, pushing ahead with one of the deadliest assaults of the crackdown that activists say has killed hundreds in the past two weeks, aimed at crushing a stronghold of dissent.

Black smoke billowed from an oil pipeline in the city that was hit in the fighting, with each side blaming the other for attacking it. Activists reported at least eight killed across the country Wednesday.

Amendments to the constitution once were a key demand by the opposition at the start of Syria’s uprising, when protesters first launched demonstrations calling for change. Assad has also talked of holding parliament elections after the referendum.

But after months of the regime’s fearsome crackdown, the opposition dismisses any talk of reform, saying that they don’t believe Assad will really loosen his iron grip on power and that his ouster is the only solution.