The former Beatles legend says his lover – who recently accompanied him on a romantic tour of America - is "wonderful" and he enjoyed every moment of their holiday together.
He said: "I'm so happy. We had a brilliant time in the US. We stayed mainly in hotels but did the whole Route 66 gig. It's an amazing thing to do – I would recommend it."
"It was great and we're so happy. I really enjoyed it. It was good to get away for a bit. We saw some places I'll never forget. But I must say it's nice to be back too."
The 66-year-old musician – who this week insisted death threats from Islamic extremists would not prevent him from playing a concert to mark the 60th anniversary of Israel – has been dating Nancy, 47, since last year.
His new romance follows a bitter divorce from charity campaigner Heather Mills, who secured a $50 million in a court settlement earlier this year. But Paul insists his love life is finally back on track."
He added: "Things are going great. We enjoy each other's company and Nancy gets on brilliantly with the family. It is still early days but we are very much together. She is wonderful."
