Yahoo!'s attempt to purchase social networking site Facebook Inc. is not moving forward, according to the Wall Street Journal.

Both companies have held talks over the course of a year, but lately the companies have not been seeing eye-to-eye. Yahoo has placed the value of Facebook at $1 billion.

CNN reports that Yahoo has been slow to close the deal because it is facing slower advertising growth and a delayed upgrade to its advertising systems.

Facebook had a reported 13.3 million U.S. visitors to the site in September.

The acquisition of Facebook would put Yahoo in position to compete with News Corp.'s MySpace and Google's YouTube on the social media front.