The striker has scored five goals in his last four games after a brace in Saturday's 4-0 win at West Brom.
"We will talk in the summer and make a decision on what is going to happen," he said.
"We haven't talked about anything relating to his contract.
"I'm delighted with the way he is performing, the goals he is scoring and the form and energy he is in at the moment. He needs to keep doing that."