Police Service of Northern Ireland (PSNI) Chief Constable Jon Boutcher has asked the secretary of state to review the Parades Commission determination allowing the Drumcree parade, BBC News NI understands.
Boutcher triggered the move under the Public Processions (Northern Ireland) Act 1998 earlier on Friday.
It comes as First Minister Michelle O’Neill confirmed she has received a letter from police investigating protests over the Drumcree parading dispute.
Portadown deputy District Master Alastair Power said there would be “serious consequences” if the Northern Ireland secretary intervened to stop the march.
It is the 13th day of deadlock between residents of the mainly nationalist Garvaghy Road and the local district lodge of the Orange Order.
The Parades Commission ruled that the march could go ahead with restrictions in place.
But the parade, from Drumcree Church into Portadown, did not happen due to a large protest on the Garvaghy Road.
On Thursday, the police said they had begun issuing letters inviting people “reasonably suspected” of committing offences linked to the protests to interview.
Unionist politicians have called for action to be taken against O’Neill and other senior Sinn Féin politicians who took part in the protests against the Orange Order march down the Garvaghy Road at the end of last month.
Under section nine of the Public Processions (Northern Ireland) Act 1998, Boutcher can make an application asking Northern Ireland Secretary Sir Chris Bryant to reconsider the Parades’ Commission determination.
Neither the PSNI nor the Northern Ireland Office (NIO) has commented on the development.
But BBC NI understands Bryant is now in the process of consulting with Boutcher and the commission.
Sources state he has not yet reached any conclusion.
Under the legislation, the minister has the power to revoke a determination, amend it, or stick by it.