The Brazilian-born Dutch centre-half is available on a free transfer this summer as his contract with FC Twente is due to expire on July 1.
Newcastle United have a long-standing interest in the player, having previously tried to sign him, and Sky Sports understands they still have an interest - although reports that a deal is close appear wide of the mark.
His agent Agent Rodrigo de Silveira Da told Sky Tyne and Wear: "At the moment there is nothing official, we were in Europe last week and have some options.
"There is interest in England, Germany, Turkey and Russia so we are going to discuss all the opportunities."
Da Silveira says Douglas is determined to book his place in Holland's World Cup squad for next year, so they need to get the decision right about his new club.
"His dream is to play in the Dutch national team at the World Cup in Brazil," he said.
"We need to find a very good club. This is the reason we are waiting."