Rail minister Jo Johnson was accused of "reneging" on commitments after failing to confirm plans to fully electrify the Manchester to Leeds route.

The Conservative frontbencher told MPs an announcement on the Transpennine route upgrade would be made later in the year - pending consideration of a Network Rail report.

He added the £2.9 billion project will include major civil engineering projects and electrification but stopped short of guaranteeing full electrification.

Shadow transport secretary Andy McDonald, who secured an urgent question in the Commons on the issue, said if investment was pulled it would "kill any notion of a Northern Powerhouse".

Insiders are reported to have said the huge cost of fixing electric cables to the rock of the Pennines, along with raising bridges, has sent the project soaring well above its £290 million estimate in 2011.

Ditching electrification would also scupper plans to send freight through the Pennines, connecting docks at Liverpool, Teesport, Immingham and Hull.

Speaking in the Commons, Mr Johnson said: "We are looking carefully at the options that Network Rail has presented to the department and will be coming out with a statement later in the year, ensuring that we deliver the highest possible value for taxpayers and also deliver significant benefit for passengers in the North of England."

Labour's Lucy Powell (Manchester Central) said: "Coming off the back of all the turmoil that we've seen on Northern rail and elsewhere recently, isn't this equivocation on the electrification of the Manchester to Leeds line just another real serious blow for people in the North, who now feel overwhelmingly, time and time again, they are getting a second-class service from this Government?"

She pushed Mr Johnson to show political leadership and say the electrification of the line is of such strategic importance that it will happen "come what may".

Mr Johnson, in his reply, said: "This Government is signalling its political commitment to the north of England by spending £13 billion on transport in the north in the years to 2020, and on allocating £2.9 billion to the Transpennine route upgrade alone."

Labour's Mike Kane (Wythenshawe and Sale East) said the reports at the weekend showed Mr Johnson was "reneging" on the commitment.

Rachel Reeves, Labour MP for Leeds West, added: "Can the minister confirm it is no longer the Government's commitment to fully electrify the route between Manchester and Leeds?"

Mr Johnson repeated the Government is awaiting Network Rail's "final options plan" about how to make best use of the £2.9 billion for the upgrade.

He added: "That will include major civil engineering projects and it will include electrification."

Chris Williamson, Labour MP for Derby North, added: "My constituents were given a solemn pledge by this Government to electrify the Midland Main Line - only for the Government to renege on those promises.

"I have to say the minister's response to (Mr McDonald) regarding the Transpennine route seems to indicate the Government is not going to proceed with the electrification of that route too.

"Does the minister not realise that this kind of reneging on solemn pledges brings the political process into disrepute?"

Mr Johnson highlighted changes to the Midland Main Line which he said would benefit passengers, including electrification work.