"This is a strategic decision that has been taken based on current business activity levels," says Siemens. "Crossrail is a very large project and, since first undertaking our initial assessment of capacity and deliverability, Siemens has won multiple additional orders. To pursue another project of this scale could impact our ability to deliver our current customer commitments - something we believe would not be a responsible course of action."\r\nIn Britain, Siemens is already working on the \u00a31.6bn Thameslink train order for 1160 emu cars, which was finalised on June 27.\r\nSiemens says it has an "excellent working relationship with the Crossrail bid team and believes that they have conducted a fair and diligent process." Siemens is already involved in the Crossrail project as it recently won a \u00a343m contract to supply signalling, communications and control systems for the line's 21km-long tunnels and nine new stations in central London. It is also providing station and line management, security, information and Scada systems.