Britain's Queen Elizabeth attends the formal unveiling of the new logo for Crossrail, which is to be named the Elizabeth line, at the construction site of the Bond Street station in central London, February 23, 2016. [Photo/Agencies]

LONDON -- London's newest crossrail, currently being built beneath the capital, is to be named the Elizabeth line when it opens to passengers in December 2018.

The name was announced Tuesday as Queen Elizabeth visited Bond Street station to view the multi-billion dollar project.

Mayor of London Boris Johnson announced the new railway would be known as the Elizabeth Line in honor of Britain's longest-reigning monarch who turns 90 this year.

The department for transport said: "The Elizabeth line will transform travel across the city, boosting the economy by billions of dollars and supporting thousands of new jobs and homes."

The new rail line will see 24 trains per hour in each direction when the central section of the railway opens.

During the visit, the Queen met a wide range of people involved in the construction, including young apprentices helping to build the railway.

The Queen became the first reigning monarch to travel on the London Underground in 1969, when she opened the Victoria line service.

In 1977, the Jubilee line was officially opened by heir to the throne, the Prince of Wales, and was named to mark the 25th anniversary of the Queen's accession to the throne in 1952.

Mayor Johnson said: "As well as radically improving travel across our city, the Elizabeth line will provide a lasting tribute to our longest-serving monarch."

Transport Secretary Patrick McLoughlin said: "It is very fitting that this vital link across our capital will be named the Elizabeth line in her honor. This is an example of British engineering at its best and will transform the way people travel across London and beyond."

When the railway fully opens, it will significantly increase London's rail capacity, carrying over half a million passengers every day.