The feasibility study was being conducted on the sections of Mumbai-Ahmedabad, Delhi-Chandigarh and Bangalore-Hubli, Member, Mechanical, Railway Board, Praveen Kumar said.
"The problem is, it (the project) has to be taken up as a national project because it will not pay back", he told reporters in response to questions on high speed trains. "The cost of the project will be so high that it will not be commercially viable initially".
So, the problem would be one of funding, Praveen Kumar said but added the consultant was expected to "find out some method".
"Some attempts are being made to get funding by public-private-partnership route. If funding is available, then only the project can be done".
He also favoured the model of states sharing expenditure, similar to shouldering burden in some other railway projects.
"Ours is a big country and we need to travel faster but then it has to pay back", Praveen Kumar said. "For high speed trains to run, there is need for dedicated tracks, and one cannot have level-crossing, and there should be grade separator," he pointed out.