The Old Trafford boss flew to Lisbon last Monday for face-to-face talks with his unhappy winger.
And Fergie was in uncompromising mood at the secret meeting, dismissing Ronaldos pleas to join Real Madrid.
Ferguson revealed: He will be a Manchester United player next year. Thats our stance he wont be sold.
The Old Trafford chief is confident he has done enough to keep Ronaldo out of Madrids cl**tches.
He said: The simple reason is that the boy is under contract. The strengths and the rights are with Manchester United.
I went out to see him in Portugal and it was very amicable.
''There were no problems so, therefore, we carry on.
Ronaldo, who is recovering from an ankle operation, had publicly welcomed Madrids interest.
Fergusons response, after returning from his holiday, was to jet to Lisbon to see what Ronaldo had to say.
The manager, in South Africa for a pre-season tour, added: The meeting went well.
''We both made our points of view about where we stand and where the player stands. Its not a difficult position for us.
I was on my holiday and I was not going to interrupt my holiday believe me!
What we have done well is to keep our position private. And what I said to Cristiano will remain private.
''There is no problem for us.
Ferguson was always going to travel to South Africa for the three-match tour without his young star because of Ronaldos Euro 2008 campaign.
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