The Iraqi government warned on Friday that its relationship with US intelligence agencies could be damaged if a report that the US spied on Prime Minister Nouri al-Maliki was accurate.
"If it is true, it casts a shadow on the future relations with such institutions," spokesman Ali al-Dabbagh said in a reference to the CIA.
"It also reflects that institutions in the US are used to spying on their friends and their enemies in the same way," he added.
A forthcoming book, entitled "The War Within: A Secret White House History, 2006-2008," by Washington Post journalist Bob Woodward, alleges the US spied on al-Maliki and other senior Iraqi officials.
The book is set for release on Monday and was the subject of a Post report on Friday.
The Iraqi government intends to raise the issue with the US and seek an explanation, al-Dabbagh said.
Woodward is well-known for his investigative reporting but also for his use of anonymous sources. He grew into national fame with his reportage on the Watergate scandal, which led to president Richard Nixon's resignation in 1974.