The Serbia international scored seven goals and made 33 league appearances last season for Juve.
"Manchester United have been interested in Krasic for two years," said Krasic's agent Dejan Joksimovic to tuttomercatoweb.com.
"They like the player but no negotiations have taken place.
"Every day Krasic is rumoured to be departing Juventus but, currently, there are no signs of this happening."
The 26-year-old joined Juve from CSKA Moscow in June 2010 and is under contract with the Serie A outfit for another three years.