The Orange Order have said they are determined to overturn a ban on completing the controversial parade at Drumcree.
Darryl Hewitt, the Grand Master of the Portadown Lodge, said in his speech at Sunday's annual march that their "resolve has not diminished".
He went on: "No-one should be in any doubt, Portadown District are in this for the long haul. We will not be deflected from seeking to achieve our objective."
Orangemen have been banned from walking along the predominantly nationalist Garvaghy Road for almost 20 years.
The parading dispute in Portadown led to scenes of violence in previous decades.
While tensions have dissipated, Portadown Orangemen continue to campaign to be allowed to walk the road.
Mr Hewitt accused the Parades Commission of "pandering to a hard-line republican agenda".
He continued: "They must go and the call from this place this afternoon is that the Secretary of State must show some mettle, and once and for all sack the whole lot of them.
"However, we attempt to complete our parade each and every Sunday - a fact that most people in Northern Ireland are not aware of.
"This has been the case since July 1998 when our late District Master Harold Gracey said that we would remain on protest until our rights have been restored."
Commissioners said there was no consensus between Orangemen and nationalist residents on the format of any potential future talks to mediate a resolution.
In the absence of any locally-agreed accommodation, the commission said there would be a "high potential for public disorder" if the parade was allowed to proceed on its notified route.
A proposal to transfer the responsibility for regulating parades from Westminster to Northern Ireland politicians was agreed in the 2014 Stormont House Agreement.
That plan, which would have seen Stormont ministers developing a new way to manage parades and protests, has yet to materialise, amid ongoing political stalemate.