The ambitious Crossrail project is now three-quarters of the way through its tunnelling process.

Officials stated 19 miles of excavating has been completed so far, removing 2.5 million tonnes of earth. The development of the new network is also said to be running on schedule and keeping to its budget constraints.

The milestone was reached after the thousand-tonne boring machine Victoria - named after the former queen of England - broke through into Whitechapel station. Work is already underway to create over a kilometre of new platform and passenger tunnels at this location.

London mayor Boris Johnson stated: "With three-quarters of tunnelling complete, we're tantalisingly close to finishing what is without doubt a monumental feat of engineering."

Meanwhile, the major focus of the project is expected to shift during the second half of the year. While the tunnelling process is set to continue, more emphasis will be placed on the task of fitting out the new stations and tunnels.