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The operators of the renowned London Underground and Paris Métro are reportedly competing for the concession to operate the metro system in Buenos Aires, known as the Subte. The contract is thought to be worth around US$3.5 billion over 10 years.

The Argentinian capital's metro is a mass transit system comprising six lines, which span a total 55km, and a 7.4km pre-metro LRT line. It has 86 stations. The network was used by 1.2 million people per day in 2017. To meet growing demand, service is increasing - 401 new metro cars have been introduced since 2013.

The first line opened in 1913 and the main routes were completed in 1944. The system was privatised in 1994. It is currently operated by an Argentinian company, Metrovías, whose concession contract expires at the end of this year.

The metro authority SBASE (Subterráneos de Buenos Aires Sociedad del Estado) launched the tender for a 12-year operation and maintenance concession in February this year. It covers the entire network plus any extensions or new lines. There is an option to extend the contract by up to three years.

Transport for London (TfL) is thought to be participating in the tender in consortium with Keolis, the largest private sector transport group in France, and Corporación América, an Argentinan conglomerate. Paris Transport Authority (RATP) has allegedly teamed up with French rail developer Alstom.

Other reported proponents are Deutsche Bahn, the largest railway operator and infrastructure owner in Europe; Bombardier, one of the largest rail manufacturers in the world, and Siemens.

Although, the participants will not be confirmed until technical bids are opened, which is scheduled for 3 July 2018. Economic offers will follow at the end of August, as SBASE aims to award the contract in October, ready for the concessionaire to begin operating the metro from 1 January 2019.

TfL's participation in the tender is thought to driven by funding problems. Following the loss of a GBP700 million (US$934.8 million) government grant and a four-year fare freeze imposed by the Mayor of London, the organisation is looking for new ways to generate additional commercial income.