Richard Haass says disputes should be resolved by dialogue
The man who will chair all-party talks later this year says politics is the only way of resolving parades disputes.
Dr Richard Haass, who is in Northern Ireland on a fact-finding trip, met party leaders ahead of intensive talks in the autumn.
He said that recent violence in Belfast was a reminder of the challenges that remain in the region.
The talks will deal with many divisive issues including parades, protests, flags, symbols and emblems.
Dr Haass, a former US Special Envoy for Northern Ireland, said disputes should be dealt with through dialogue.
"Disagreements are fine, disagreements are to be expected, but again disagreements are to be dealt with verbally and done within a legitimate and accepted political process," he said.
Speaking in the House of Commons on Wednesday, Prime Minister David Cameron said: "I think it's very important that we see responsibility on both sides in Northern Ireland and we do take steps in terms of making sure that these marches can go ahead in a way that respects that fact, that communities should be good neighbours to each other.
"That's what's required in Northern Ireland."
Deputy First Minister Martin McGuinness said Mr Haass was well qualified to chair the talks.
"We've all met him in the past. I think we have all been impressed by him," he said.
"He is someone who has an empathy with the situation here, someone who wanted to do this whenever we asked him and one of the first points that he made was that he didn't want a salary, so we're dealing with someone who is very genuine."
First Minister Peter Robinson said Dr Haass was the "first choice" for all the parties to chair the talks.
The Orange Order's Grand Lodge has said that it will "willingly and actively participate in the Haass initiative".
The order says it will do so with the aim of replacing the Parades Commission with "a better regulatory system".
BBC Northern Ireland political editor Mark Devenport described Dr Haass' visit as a "fact-finding exercise".
"The fact that violence is still continuing on the streets shows the kind of scale of the task that faces him."
Dr Haass served as US envoy to Northern Ireland from 2001 to 2003.