The public inquiry into the proposed M4 relief road around Newport will begin on 28 February.
Economy Secretary Ken Skates wanted updated traffic projections to strengthen the Welsh Government’s case of the new preferred “black route”.
UK government predicts slower growth in traffic than previously expected but Mr Skates has said the Department for Transport data was wrong and undermined the road’s case.
Earlier, a five-year multi-billion pound infrastructure investment for Wales was outlined by Mr Skates.
The Economy and Infrastructure Secretary was at Cardiff airport setting out his vision for a modern, integrated transport network that delivers for communities right across Wales.
The investment, which includes major improvements to the M4, A55, A40 and A494, the delivery of a South Wales Metro, the development of a North Wales Metro, a new rail franchise, a ports development fund, the development of a third Menai crossing, improved, more sustainable bus services and more, will be the largest Wales has seen in a generation.
At a speech to a transport and business audience at Cardiff Airport this morning, the Economy Secretary will make clear the importance of working together to maximise the impact of this historic funding, to ensure maximum benefits for the whole of Wales.
Speaking ahead of the event Ken Skates said, “Our historic, multi billion pound investment shows how serious this Welsh Government is about delivering a world class transport system in Wales – one that sustainably connects people and communities to jobs and services and drives our economy forward.
“Our network holds the key to delivering a prosperous Wales, to ensuring our general health and well being and building cohesive communities. Our collective challenge must be to use this billion pound investment creatively and collaboratively to sustainably develop a world class transport system that delivers the very best results for Wales.
“I also want to establish a better informed, better designed, long-term, evidenced-based approach to the planning of our transport network and the National Infrastructure Commission, which we are proposing, alongside an updated Welsh Transport Planning and Appraisal Guidance will help ensure this.”
On rail and buses the Economy Secretary said he wanted to be smarter about how it funded local bus and train services, with better information for passengers, smarter ticketing and genuinely regional transport planning, and ongoing work towards a metro in North and South Wales.
He also said he would use the new Wales and Borders franchise, from October 2018 as an opportunity to plan for huge projected growth of rail passenger numbers and prepare for the future in a clear and clever way.
The Economy Secretary added, “In terms of major road improvements, I am publishing full technical, economic and environmental report on my review of the M4 scheme and can announce that the public inquiry into the M4 will take place on 28 February 2017, with a pre-inquiry meeting held on 27 January.
“On congestion solutions for the A494 and A55, the consultation will take place in March 2017. This will look two proposals for the Deeside Corridor project, either of which will require investment upwards of £200m – the largest Welsh Government investment on these roads since they were first built.
“This whole agenda brings with it undoubted challenges but it also presents fantastic opportunities to for a bigger, better, multimodal and integrated network that meet the needs of people right across Wales.”
In his speech the Cabinet Secretary will call for greater devolution of transport powers to Wales, including funding for rail infrastructure and new powers over Air Passenger Duty.