Labour would renationalise the railways, its conference has been told, although Keir Starmer will continue to face pressure after delegates unanimously passed union-backed motions urging public ownership of Royal Mail and inflation-proof pay rises.

The party leadership avoided a potentially divisive split on public ownership of energy and water firms, as the leftwing campaign group Momentum accused it of “rigging the system” to water down a related motion.

But delegates unanimously passed a motion expressing support for Labour MPs attending picket lines, in effect rebuking Starmer after he sacked Sam Tarry as shadow transport minister in July for giving unauthorised media interviews from an RMT demonstration.

Earlier, delegates got to their feet and applauded as Dave Ward, the general secretary of the Communication Workers Union (CWU), sounded a call from the conference stage to support striking workers and said he hoped to see the Labour leader on a picket line in the coming weeks.

“We’ll get a bacon butty ready for him. Keir, let us know: is it brown or red sauce?” Ward said. “Our members want to know: does this Labour conference stand with your posties? And if you do, are you going to be on the picket lines when we take our next strike action on Friday and Saturday of the coming week?”

He moved a motion aimed at committing the next Labour government to bringing back Royal Mail into public ownership and reuniting it with the Post Office, which was passed.

Nationalisation remains a sensitive topic in the party. In its 2019 manifesto under Jeremy Corbyn, Labour committed to bringing rail, mail, water and energy into public ownership, but Starmer and his shadow chancellor, Rachel Reeves, have withheld endorsement of bringing key industries into public hands.

However, the shadow transport secretary, Louise Haigh, gave a delegate-pleasing restatement of Labour’s support for bringing the railways back into public ownership as contracts expire, in what was regarded as a victory for her own lobbying.

Eliciting sustained applause, Haigh also said Labour would give communities the power to set bus routes and fares. She said: “We will cast aside the tired dogma that has failed passengers. We will improve services and lower fares. And, yes, conference, Labour in power will bring our railways back into public ownership where they belong.”

Campaigners inside Labour will continue to press for the party to bring energy as well as water into public ownership, after controversial last-minute procedural moves meant the position was not included in a motion. They pointed out the warm reception from the conference when it was mentioned in speeches.

Delegates from Momentum alleged they were not told about a meeting to agree a motion on nationalisation that they were entitled to attend.

One of them, Don Lindsay, from Barrow and Furness Labour party, said from the conference stage that a call for a “socialist, green new deal” had been “cynically excluded from debate”, and he drew applause when he added: “Our CLP believes that this transformation of our whole economy, expanding public ownership so we can plan a just transition, must be absolutely foundational to Labour’s green ambitions.”

He urged support for motions on pay and rail nationalisation, but added: “Remember that at every turn this conference’s so-called democracy has been rigged.”