London & Continental Railways will subsequently be sold, possibly to German rail operator
The European Commission has approved a UK plan to give a £5.2bn boost to Eurostar and the Channel Tunnel Rail Link (CTRL), which is managed by state-backed holding company London & Continental Railways (LCR).
The CTRL or High Speed One links the channel tunnel with St Pancras station.
The money will be used to refinance LCR and split the firm's infrastructure and transport functions before a sell-off. German rail firm Deutsche Bas has expressed interest in the sale.
LCR is made up of a consortium whose members include National Express and Bechtel, but the money from any sale would go to the Treasury, which underwrote the £6.1bn-worth of debt. The government passed a bill to allow the nation to profit from the sale in 2008.
Former LCR chief Rob Holden is now in charge of the Crossrail programme.
A spokesman for rail union RMT said it was furious at the sale of the “UK's only vertically integrated railway line” to the Germans.