Madonna tells US fans to value freedom

Philadelphia - As she kicked off the US leg of her MDNA Tour in Philadelphia, Madonna said she was happy to party in the USA after touring Europe for three months.

The pop icon told the crowd on Tuesday they should "never forget how lucky you are to live where you live and to have the freedom that you have".

She made the comments after talking about punk-rock group Pussy Riot's recent arrest in Moscow after the female band performed a "punk prayer" against Russian President Vladimir Putin in Moscow's main cathedral.

Madonna said it was no coincidence that she opened her US tour "where the Declaration of Independence was signed". Then the 53-year-old yelled: "We are in the land of democracy."

She also told the crowd: "Don't get fat and lazy and take that freedom for granted."