The joint venture partner of collapsed infrastructure services group Carillion says it has made contingency plans for their contracts which include work on new high-speed rail line HS2.

Listed construction group Kier told the Stock Exchange today it was now working with clients in order to avoid an interruption of service.

Last July, the Department for Transport awarded a £1.4 billion contract to a joint venture comprising Kier, Carillion and French civil engineering group Eiffage to build some of the tunnels which will make up the first phase of HS2 between Birmingham and London.

The joint venture, called CEK, will build from North Portal Chiltern Tunnels to Brackley and Brackley to Long Itchington Wood Green Tunnel South.

All three firms were forced to give assurances they could step in to deliver on the work if one of the partners collapsed.

But the contract was thrown into doubt today when it emerged that Wolverhampton-based Carillion had collapsed and been placed into compulsory liquidation.

Kier said in a statement: "Kier Group notes today's announcement relating to Carillion.

"Kier currently operates joint ventures involving Carillion on HS2 and the Highways England smart motorways programme.

"We have put in place contingency plans for each of these projects and are working closely with clients so as to achieve continuity of service.

"Following today's announcement and after a short period of transition for these contracts, we do not expect there to be an adverse financial impact on the group arising from these joint venture contracts."

A spokesman for Kier said the company would be making no further comment at this stage on the collapse of Carillion.

A HS2 spokesman described Carillon going into liquidation as "clearly disappointing for them and the wider UK construction industry".

He added: "We are continuing to discuss with Kier and Eiffage the implementation of contingency plans.

"Work will continue as planned with no unnecessary or additional exposure to the taxpayer."

Eiffage has been contacted for a comment but had not responded at the time of publication.