Syria: Obama signs off on sanctions hitting Syria, Iran

The sanctions freeze any assets the groups have in US jurisdictions and bar Americans from business with them.

Mr Obama authorised the penalties in the wake of a bloody crackdown on anti-government dissent that has left some 500 people dead, US officials said.

Two relatives of President Bashar al-Assad were targeted by the sanctions.

The sanctions name Syrian intelligence chief Ali Mamluk; Mr Assad's cousin Atif Najib, the former leader of the Political Security Directorate in Deraa Province; and Maher Assad, Mr Assad's brother and commander of the Syrian Army's Fourth Armored Division, which is accused of carrying out the worst atrocities in the southern city of Deraa.

In Deraa, dozens of people are reported to have been shot dead in recent days.

President Assad was not among those targeted in the sanctions, but he could be named later if violence continues by government forces against pro-democracy protesters, US officials said on Friday.

Activists have reported that some 500 people have been killed in the protests, which have been taking place for over six weeks, against the Syrian government.

The executive order signed by President Obama gives the US "new tools to target individuals and entities determined to have engaged in human rights abuses in Syria, including those related to repression", the White House said in a statement.

'New tools'

The executive order signed by President Obama gives the US "new tools to target individuals and entities determined to have engaged in human rights abuses in Syria, including those related to repression", the White House said in a statement.

US officials said the sanctions were intended to send a message to the Syrian people that those responsible for the abuses must face consequences for their actions.