A different source said that the talks have stalled over "just a gap."
Yahoo! Sports had earlier reported the snag in contract talks.
As a restricted free agent, Green is allowed to sign an offer sheet with another team but the Warriors have seven days to match the offer if they so choose.
Green, 25, had a career year for the Warriors, starting 79 games for the NBA champions, who finished with the best record in the West. He averaged career highs in points (11.7), rebounds (8.2), assists (3.7), blocks (1.3), steals (1.6) and shooting percentage (44.3), and finished runner-up for Defensive Player of the Year.
He also performed well in the playoffs, averaging 13.7 points, 10.1 rebounds and 5.2 assists for the NBA champs. Green recorded a triple-double in the Warriors' clinching Game 6 win over the Cavaliers.
Green's impact goes well beyond stats, though, with his tenacity, intensity and hustle all key elements of his game. He's a bit of a do-it-all utility power forward who can play multiple positions, shoot the 3 effectively and defend all over the floor. Green was the anchor of the league's best defense, with an impressive individual defensive rating of 96.0.
The Warriors selected Green 35th overall in 2012, landing an unexpected impact player in the second round. He appeared in 79 games as a rookie (one start), averaging 13.4 minutes per game, but burst out in the Warriors' first-round upset of the Denver Nuggets. He blossomed into a significant rotation player in his second season, and built on that development to turn into a potential maximum-contract player.
As a second-round pick, Green has been one of the league's biggest bargains the past three seasons, making only $915,243 this past season. He averaged 11.7 points, 8.2 rebounds and 3.7 assists with a PER of 16.43.
ESPN.com's Royce Young contributed to this report