The statement comes after the Wall Street Journal reported that the two companies were close to announcing a deal.
In a statement, Gamesa said: "As of today, no decision has been made and no agreement has been reached."
Back in January, Gamesa and Siemens said they were discussing a possible deal to create the world’s biggest wind power business. However talks have now stalled due to concerns with Gamesa’s links to an existing joint venture with Areva.
Talks are ongoing.