Scotland will fail to meet its ambitious environmental targets unless it provides a “world class” rail service, unions have claimed.

ScotRail will revert to public ownership in March after SNP ministers previously ripped up a contract with current operators Abellio following years of complaints from passengers.

Now the big four unions representing thousands of workers employed on the railways have teamed up to publish a report looking at how the franchise can be improved in the long-term.

It calls for the publicly owned system to be “clean, green, affordable, well-staffed, punctual and reliable” if more Scots are to be tempted to leave their cars at home in favour of taking the train.