The Government is "not backing away" from the High Speed 2 rail link between London and the north, says the Transport Secretary.
A new housing estate in Mexborough could be demolished to make way for a new proposed route through South Yorkshire.
Chris Grayling will say the case for the controversial project is "as strong as ever" as the rail network rapidly approaches "crunch-point".
Creaking Victorian lines will be unable to cope with growing demand as the country's population continues to grow, he will tell a HS2 conference.
In a speech, Mr Grayling will say: "We're not backing away from HS2. The case is as strong as ever.
MPs warned last month that ministers must set out a realistic timetable for delivering HS2.
The Public Accounts Committee (PAC) was "not convinced" that the target for completing phase one between London and the West Midlands by December 2026 will be met.
Its report also warned that cost estimates for phase two, which takes it from Birmingham to Manchester and Leeds, are "still volatile" and exceed available funding by £7 billion.
Mr Grayling will announce £70m of funding for road safety and support for communities affected by the line.
He will say: "We need HS2 now more than ever.
"We need it for the capacity it will bring on the routes between London, the West Midlands, Crewe, Leeds and Manchester, as well as the space it'll create elsewhere on our transport network.
"We need it for the boost it will give to our regional and national economies.
"And we need it for the jobs it will create, and for the way it will link our country together.