Company logo of Syria's state-owned mobile firm
The European Union imposed sanctions on Syria's main mobile phone operator Syriatel and its largest private company, Cham Holding, on Saturday to intensify pressure on President Bashar al-Assad.
The sanctions also include a television station, Addounia TV, and three construction and investment firms linked to the Syrian military, the EU's Official Journal showed.
The EU's latest move complements an embargo on crude oil imports to the bloc and a ban on European firms investing in Syria's oil industry, which was agreed this week, and aims to reduce Assad's access to funds as his forces continue to kill pro-democracy protesters.
European governments began imposing sanctions against Assad's government in May but took a cautious approach initially, focusing on officials linked to the crackdown.
Critics said the caution was linked to concerns in some EU capitals about commercial interests. Anglo-Dutch Royal Dutch Shell and France's Total, among others, have significant investments in Syria.
The U.S. has imposed more far-reaching sanctions than the EU, freezng all Syrian assets in the U.S. and barring U.S citizens from making new investments in Syria.
Observers say EU measures can have more bite because Europe's commercial links with Syria are more extensive. EU diplomats say additional measures could be in the pipeline if there is no change in Syria.
Assad's military crackdown has killed at least 2,700 people, according to the United Nations. Experts say the economic sanctions are beginning to take a toll on the economy.
The country's oil exports -- most of which had gone to Europe -- have dwindled and the government is struggling to buy the petrol it needs.
Syrian businessmen said on Saturday that imports of most foreign manufactured goods, but not raw materials and grains, had been banned to preserve foreign currency reserves.
Targeted sanctions against Syrian officials, business executives and companies, such as those imposed on Saturday, serve as a warning to Syria's elite and could, in time, help weaken the support they give Assad, industry experts said.
"The EU is being quite strategic here, seeking to fracture the strength of the regime," said Julien Barnes-Dacey, a Middle East expert at Global Risk Analysis.
"They are saying to the larger business community: 'We're coming after you.'."
Diplomats argue Syria's fragmented opposition and the significant support of industry for Assad complicates western efforts to isolate him.
Since its first round of sanctions, the EU has targeted more than 40 Syrian officials and several companies and other entities with asset freezes and travel bans.
Syria's information and justice ministers were added on Saturday, with the EU citing their support for arbitrary arrests and detention among the reasons for sanctions.