A shed for bats that is costing more than £100 million is the “tip of the iceberg” in the “failure” of HS2’s delivery, Transport Secretary Louise Haigh has said.

Ms Haigh has said that the “shocking example epitomises the complete lack of efficiency” that has been found on the rail project.

Earlier this week it was reported that HS2 Ltd is spending more than £100 million building a “shed” for bats to appease Government adviser Natural England, despite there being “no evidence that high-speed trains interfere with bats”.

All bats are legally protected in the UK, Ms Haigh said on Saturday that while she recognises the “importance of meeting legal obligations” there must be a “sensible balance” when it comes to costs.

She said in a statement: “This shocking example epitomises the complete lack of efficiency we have uncovered on HS2 and is yet another example of why I’ve launched an urgent, independent review to get a grip on costs.

“Since becoming Transport Secretary, I have seen up close the scale of failure in HS2’s project delivery and this is just the tip of the iceberg.

“While I fully recognise the importance of meeting legal obligations we must strike a sensible balance, and I will not standby and allow costs to spiral in this way.

“I have reinstated direct ministerial oversight of the project and will be looking at what other systemic reforms we can put in place to ensure public money is put to good use and not wasted.

“Through this tighter control, we will remove barriers that lead to project delays and eye-watering additional costs to taxpayers.”

HS2 Ltd’s chairman Sir Jon Thompson told a rail industry conference earlier this week about the bat protection structure in Buckinghamshire.

He said: “We call it a shed.

“This shed, you’re not going to believe this, cost more than £100 million to protect the bats in this wood.”

The curved structure will run for around one kilometre (0.6 miles) alongside Sheephouse Wood, creating a barrier allowing bats to cross above the high-speed railway without being affected by passing trains.

After receiving the go ahead from Natural England for the design, HS2 Ltd was forced to spend “hundreds of thousands of pounds” on lawyers and environmental specialists because the local council did not approve the work, Sir Jon said.

He said he won the planning permission by going over the heads of the local council and claimed this is an example of the UK’s “genuine problem” with completing major infrastructure projects.

Last month it was announced that ministers will oversee the building of the rail line and there will be regular meetings that she will attend alongside Rail Minister Lord Peter Hendy and the Chief Secretary to the Treasury Darren Jones that will examine the progress of the project and its costs.

There will be reports on HS2 every six months to “ensure complete accountability and transparency”.