Legislation allowing phase 2b of HS2, connecting the line from the Midlands to Manchester and Leeds via Sheffield and the East Midlands, was intended to be introduced in 2019, transport secretary Chris Grayling said last year.
However, it has emerged that the hybrid bill, which if passed would grant planning permission for that stage of the project, will not now be tabled until 2020.
A spokesman for the DfT said the delay would not impact on the delivery of the project, which is still intended to open in 2033.
The DFT said the hybrid bill was being paused because the governwant wanted to fully consider the impact on HS2 of the separate Northern Powerhouse Rail project, which would travel from east-to-west and link Liverpool, Manchester, Leeds, Sheffield and Newcastle.
The spokesman said: "To maximise the huge potential of HS2, it is important to take full account of the emerging vision for the other transformative project of northern powerhouse rail.
"Phase 2b of the railway will connect the great cities of the north to boost jobs, housing and economic growth, and remains on track to open in 2033.
"We will update Parliament as part of our consultation this autumn."
The full HS2 Y-shaped route will link London, Birmingham, Manchester and Leeds.
Phase 1 between London and Birmingham was given formal approval by Parliament in February 2017, while the bill for phase 2a, which runs from from Birmingham to Crewe, is currently going through parliament.
Judith Blake, the leader of Leeds City Council and a member of the West Yorkshire Combined Authority, said: "The DfT have assured us that timetabling for project delivery is still the same and it is imperative that doesn’t change.
"However, any delay in the process which will deliver HS2 to the North is concerning and it is essential that this does not have a knock-on impact on the timetable for construction or the opening of the eastern leg.
"There’s a great deal of work going on behind the scenes in making sure we’re HS2 ready and we’ll shortly be submitting our strategic outline business case to government detailing our vision for Leeds Station.
"Any additional time in the parliamentary process must be used to ensure that HS2, serving a remodelled Leeds station, is properly integrated into the wider transport network to maximise the benefits to our region and the wider North."
The news came as Labour today announced that, if it formed a government, it would commit £10 billion to build an east-west rail link across the north of England, which it called "Crossrail for the North".
According to a party statement, the line would travel from Liverpool Lime Street to Manchester, then on to Leeds and finally Hull.
Meanwhile, it was announced on Friday that the opening of Crossrail, linking east and west London, which was due at the end of this year, would be delayed until next year.