London hosted the inaugural season finale in Battersea Park, but its five-year deal ended after just the second event because of local criticism.

That meant London fell off the FE calendar for 2016/17 and it is not part of the 11-city schedule for the upcoming 2017/18 season.

FE is keen to host a race on the streets of the city, having originally envisioned a circuit that would incorporate Trafalgar Square and The Mall, but that plan has so far failed to turn into anything tangible.

Asked by Motorsport.com about the prospect of the London round, a spokesperson for city mayor Sadiq Khan revealed he is "keen to see a London ePrix return to the capital".

They also confirmed "officers remain in discussion with the organisers of Formula E to identify suitable venues in London".

Getting permission to use the desired locations is the major hurdle for FE to clear.

FE CEO Alejandro Agag told Motorsport.com last month that the championship had not had "a positive reply" from the board of The Royal Parks.

That body is responsible for sanctioning the use of The Mall, which is the stretch of road that runs between St James's Park and Green Park and leads up to Buckingham Palace.

A spokesperson for The Royal Parks told Motorsport.com it had "not received a formal request to host this event".

Agag said FE is "going to keep trying" to make a London street race a reality, and said he had no deadline in mind to bring the race back.

"My time for London is any time," he said. "We're going to wait, or we won't do it. It's not mandatory. We would love to do it but we want to do it in the right place."

London is a notable absentee from an impressive 2017/18 FE calendar that includes events in the capital cities of Chile, Mexico, Italy, France and Germany.

It also has races in Hong Kong, Marrakech, Sao Paulo, Zurich, New York and Montreal.

Although London remains FE's preferred location, Agag revealed it is not the only option for a UK race: "I know we're talking to a couple – we're open. For now we're working on London, but the other options are also possible."

He added: "We just need one or two tweaks and we have the perfect calendar. We're almost there."

Though it no longer has a race, Britain has played a key part in the early seasons of FE.

Several teams are based out of FE's complex at Donington Park, while Virgin, Techeetah and NIO have all set up new offices in Britain.

FE also has a logistical hub at Donington and its main base is in London – although Britain's planned exit from the European Union could force FE to move those offices overseas for tax/revenue purposes.