The agent of Borussia Dortmund striker Robert Lewandowski has warned Manchester United and Bayern Munich of a new rival for the Pole.

United and Bayern are battling for Lewandowski's signing ahead of the summer market.

But his agent, Cezary Kucharski, says Lewandowski would welcome the chance to speak with Real Madrid.

"If (Real Madrid president) Florentino Perez was to ask for his (Lewandowski) number, I'd give it to him," said Kucharski.