Kranjcar is on the periphery at White Hart Lane and started just two games in the league for Spurs last season.
Sunderland boss Steve Bruce acknowledged his interest in Kranjcar last week, despite making 10 signings already this summer.
He could now bring in Kranjcar on either a loan or permanent deal, with the player's representative Adrian Aljai feeling the move is the best solution for the 27-year-old.
"We are about to close a deal with Sunderland," Aljai was quoted by the Daily Express.
"I believe that is the best solution for Niko."
Kranjcar joined Tottenham from Portsmouth two years ago and scored Spurs' winner away to Sunderland last season.
Source: Team Talk
Source: Team Talk