Image caption Officials thought 80% of 16-18 year olds would use the pass, but fewer than 10% did.

There are concerns millions of pounds in public money have been wasted on the setting up of a Welsh Government-funded discount bus pass for teenagers.

MyTravelPass cost almost £15m during a 19-month trial but the pass needed just £1m a year after it was fully launched.

An audit report said officials thought 80% of 16 to 18-year-olds would use it, but less than 10% did during the pilot.

The Welsh Government said the pass had encouraged more young people to use buses.

In the report, Adrian Crompton, auditor general for Wales, said there were "obvious questions" about value for money.

Plaid Cymru and Tory AMs raised concerns over whether public cash was wasted.

MyTravelPass was launched as a trial in September 2015, offering a third-off bus travel for 16 to 18-year-olds.

The Welsh Government, which agreed to set-up the pass in a budget deal with the Welsh Liberal Democrats, budgeted £14.75m for the pilot which ran until March 2017.

Most of the cash - £14.21m - went to bus operators in compensation. After ministers decided to extend the scheme beyond the pilot, just £790,000 went to bus firms that year, with a total of £1.09m budgeted in 2017-18.

The Wales Audit Office report said the fall in cost reflected the fact that, after March 2017, bus firms' compensation took into account how much the pass was being used, using data from electronic ticket machines.

Image copyright Mike Dean (Eye Imagery) Image caption Former first minister Carwyn Jones launched the scheme in 2015

It had been hoped that a smartcard scheme would be in place during the pilot to measure use, but this proved not to be possible and operators were compensated instead based on a formula.

Ministers' permission was not sought for the change.

Negotiations with bus firms were also made difficult, officials told auditors, by the fact the budget for the scheme had been declared public.

It had been announced as part of the political agreement between the Welsh Government and the Welsh Liberal Democrats in 2014.

Initial costings assumed 80% of 16 to 18-year-olds - 90,000 people - would take up passes, but fewer than 10% applied by the end of March 2017.

Image copyright Welsh Government Image caption A plan to extend MyTravelPass to 21-year-olds is currently delayed

A plan to extend the scheme to 21-year-olds - with an increased £2m budget - was due to take effect last December but is currently delayed.

Plaid Cymru shadow cabinet minister for economy and finance, Rhun ap Iorwerth AM, said: "The government have either overspent on a project irresponsibly, wasting millions of pounds in the process, or they've failed to get a potentially effective discount travel scheme off the ground."

"If the Welsh Government thought 80% of young people would participate in the scheme but only 10% actually did, then it raises serious questions and indicates a complete failure on the government's part."

Tory AM Nick Ramsay, chairman of the public accounts committee, said: "I am concerned public money has been wasted here.

"While the scheme costs are now much lower, it is also clear that the scheme has not attracted the level of interest from young people that was first envisaged.

"This suggests that there are important lessons to learn for the marketing of the scheme as it is extended to cover 19 to 21-year-olds."

A Welsh Government spokesman said: "The report recognises the pre-announcement of the scheme's funding before negotiations had taken place with the bus industry impacted on the initial cost.

"MyTravelPass has driven an estimated 1.344m discounted journeys in 2017-18, encouraging more young people to use the bus for more journeys, reducing road congestion and improving air quality."