The Spanish striker has proved a hit in Gelsenkirchen since arriving from Real Madrid in 2010.
The 34-year-old's current deal runs out at the end of the season and he is weighing up the offer of a one-year extension.
"There is still no inclination, there is still no decision," Heldt was quoted as saying by Kicker.
"For Raul it is a fundamental decision. He has to talk with his family about whether is makes sense or not."
Raul is still a key part of the Royal Blues side and has started 27 of their 28 Bundesliga games this season, scoring 12 goals.