Drivers have been warned to expect delays of more than an hour after animal rights protesters moved onto the M57 motorway.
Traffic was stopped both directions between junction 1, Manchester, and J2, Prescot, after a small group protesters dressed in pink reportedly occupied the northbound road.
Traffic management Inrix said: "All traffic being temporarily held and stationary traffic due to demonstration on M57 in both directions from J1 M62 J6 (Tarbock Island) to J2 A57 Liverpool Road (Prescot)."