Hamilton's long-term McLaren contract is due to expire, but it was expected that the 27-year-old would stay with the team that nurtured him since childhood.
In Canada last weekend, however, the Woking based outfit's executive chairman Ron Dennis hinted all is not well regarding the contractual talks.
"Where he can go, he's going to look at that, (and) we're going to look at who's available," he said.
As one of F1's very best drivers, Hamilton must only be contemplating a switch to another top team -- like reigning world champions Red Bull.
But the energy drink team's Marko said: "That Hamilton is considering his alternatives is fairly clear.
"But it has to fit with the team structure," he told Germany's Sport Bild. "It doesn't matter if you're the fastest driver or not if it doesn't fit with the team."
Marko is obviously referring to the fact that, with Sebastian Vettel already on board, Red Bull is in no need for someone who is so obviously a 'number 1'-type driver.
The same is true at Ferrari, not to mention Hamilton's 2007 clashes with Fernando Alonso.
It doesn't matter if you're the fastest driver or not if it doesn't fit with the team.
So what about Mercedes? Norbert Haug hints that the door is open.
"It is no secret that Lewis is a part of the Mercedes family," the German marque's motor racing vice-president said.
But if money is an issue at McLaren, amid speculation the team is prepared to pay him $150 million over the next five years, then it will most certainly also be an issue at lower-budget Mercedes.
Writing in O Estado de S.Paulo newspaper, Brazilian correspondent Livio Oricchio said it is fairly obvious that Hamilton is staying put at McLaren.
"There's much more speculation outside of the team than inside the team," team boss Martin Whitmarsh is quoted by Sky Sports.
"I think it's very clear that we enjoy working with Lewis. I think Lewis enjoys being in this team.
"So we have full expectation of that continuing."