Shootings and a bombing have killed at least seven more people in Iraq as a major surge in violence there continues.

Today's deaths came after the US condemned a wave of car bombings which killed nearly 80 people across Iraq yesterday, saying those who had attacked civilians during celebrations marking the end of Ramadan were "enemies of Islam".

Bombs ripped through markets, shopping streets and parks late on Saturday as Iraqis were out celebrating Eid al-Fitr, the end of the Muslim fasting month.

Eighteen months since the last US troops withdrew, Sunni Islamist militants have been regaining momentum in their insurgency against Iraq's Shia-led government.

The attacks targeted mainly Shia districts and the renewed violence has raised fears Iraq could relapse into the sectarian bloodbath of 2006-2007.

The civil war in neighbouring Syria has aggravated tensions further and Iraq's Interior Ministry has said it is facing an "open war".

"The United States condemns in the strongest possible terms the cowardly attacks today in Baghdad," the State Department said.

"The terrorists who committed these acts are enemies of Islam and a shared enemy of the United States, Iraq, and the international community," the statement continued. 

It said the US would work closely with the Iraqi government to confront al Qaeda and discuss this during a visit of Iraqi Foreign Minister Hoshiyar Zebari next week to Washington.