YAHOO Inc plans to lay off more than 600 employees as soon as today, two sources familiar with the situation said yesterday.

The cuts would represent between 4 percent and 5 percent of the Internet portal's overall staff, which totaled 14,100 at the end of September according to Yahoo's website.

The layoffs come two years into Chief Executive Carol Bartz's tenure as Yahoo works to grow its revenue amid tough competition from Google Inc and Facebook.

Technology blog AllThingsD wrote earlier this month that Yahoo planned to cut 650 employees, and the New York Times newspaper reported yesterday that the cuts could take place as soon as today.

A source familiar with the situation said the New York Times report was accurate and that the cuts would mostly be in Yahoo's product group. Another source told Reuters that Yahoo planned to cut between 600 and 700 employees from the product group today.