Scotland's latest push to overhaul intercity railways must be about more than "money-grubbing," a leading union has warned.

Transport union RMT offered a note of caution yesterday in the wake of pressure groups' calls for "a rail revolution."

Umbrella body Transform Scotland's newly launched "intercity express" campaign has pressed Scottish ministers for increased investment in the nation's rail infrastructure, with demands ranging from electrification and doubling of rail lines to a direct rail link between Perth and Edinburgh, all in a bid to reduce travel times.