Lukaku's future at Stamford Bridge continues to be shrouded in doubt amid speculation linking him with a switch to La Liga champions Atletico Madrid.
The Belgium international is reportedly being lined up by Atletico as a prospective replacement for Diego Costa, who is heavily tipped to replace him in West London.
"He asked me about the Spanish league and what our league is like. He is very interested in other leagues, like the Italian one and ours," Robles, who played with the Belgian at Goodison Park, told AS.
"Lukaku is the sort of player Cholo [Atletico coach Diego Simeone] likes. His characteristics, desire, dedication and strength are exactly what Simeone wants.
"Apart from being physically strong he is also very technical because he is such a complete forward. If Atletico do end up signing him, he would be a great addition."
Lukaku is contracted to the Blues until 2016.