The Prince's speech

Prince Harry during training for the Walking with the Wounded expedition. Photo / Pool

Prince Harry says he'll be careful not to offend Queen Elizabeth with his wedding speech honouring his older brother Prince William.

He has told Good Morning America that he'll have to be selective in what he says because his grandmother will be in the audience at the April 29 royal wedding and at the reception to follow.

The interview aired yesterday as Harry continued an Arctic charity trek in support of wounded servicemen.

He also welcomes Kate Middleton into the royal family, saying that she and William are a perfect match.

He admits that some doubted whether the marriage would ever take place, hinting that William had taken a long time to propose.