According to The London Evening Standard, Chelsea are interested in re-signing the Belgium international striker this summer.
The Mirror have credited Manchester United with an interest in the former Chelsea striker.
Hazard, who can operate as an attacking midfielder or as a winger, plays with Lukaku for the Belgium national team.
The 25-year-old former Lille star does not know if he will play with the 23-year-old striker at Chelsea next season.
"I don't know, I don't want to talk about this,” Hazard told Sky Sports when asked whether he could be playing alongside Lukaku at Chelsea next season.
“But Romelu is a big striker, he's a good guy and a good friend of mine. It's always good to play with the best in the world."
Lukaku has scored two goals and created one chance in two matches for Belgium at the ongoing Euro 2016 finals in France so far.
The Everton striker has a pass accuracy of 81% and a shot accuracy of 75%, and has won two headers.
During the 2015-16 season, the former Anderlecht striker scored 18 goals and created 51 chances in 37 Premier League matches for Everton.
The Toffees failed to finish in the top 10 of the Premier League last season, but they will be determined to push for a top-six spot in the table during the 2016-17 campaign.