It emerged that Ronaldo held secret talks with Paris Saint-Germain president Nasser Al-Khelaifi before Madrid retained the Champions League by beating Juventus last month, and that has re-ignited speculation over the possibility of a return to United.
The 32-year-old left Old Trafford for Madrid in 2009 after six seasons in English football.
Mourinho coached Ronaldo at the Bernabeu for three years and the two men share the same agent, Jorge Mendes. But he believes that prising the current World Player of the Year away from Madrid is beyond United's capabilities.
'I'm not going to waste my time thinking about players who are mission impossible,' said Mourinho.
Read more: http://www.dailymail.co.uk/sport/football/article-4700556/Cristiano-Ronaldo-return-impossible-Jose-Mourinho.html#ixzz4n1C0rfBx
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