F1's Fernando Alonso began Toyota 2018 LMP1 testing this week

Alonso's 2018/19 World Endurance Championship campaign, which will encompass his Le Mans 24 Hours debut, was announced on Tuesday.

He joined Toyota's pre-season preparations at the Aragon circuit in Spain the same day, as Toyota commenced three days of endurance testing that included night-time running.

Alonso was joined at the test by four other 2018 race drivers and the man he has replaced in the #8 TS050 HYBRID, Anthony Davidson.

Sebastien Buemi, who will share the #7 Toyota with Alonso and Kazuki Nakajima, was absent because of the birth of his second child Theo.

This was Alonso's first experience of the 2018 Toyota, after he drove last year's at the end-of-2017 Bahrain 'rookie test' (pictured below).

It was also Toyota's first test since shaking down the 2018-spec car at Aragon in early January.

A spokesman for Toyota said the test "went well" and that the team "had no issues".

Two more tests are planned before the WEC's traditional pre-season test at Paul Ricard at the start of April.

Before joining Toyota's pre-season programme Alonso's LMP1 experience was limited to his Bahrain outing.

He has also tested and raced United Autosports' LMP2 Ligier in last month's Daytona 24 Hours, although myriad problems consigned the car he shared with McLaren F1 reserve driver Lando Norris and Phil Hanson to 38th.

According to Toyota, Alonso's WEC commitment will include every round of the 2018/19 superseason that do not clash with the F1 calendar.

Toyota's home race at Fuji is currently the only affected round, although it is understood the date of the WEC race could change to allow Alonso to take part.