Robert Kubica pulls out of racing for ByKolles LMP1 team in WEC

Kubica had been due to make his full-time circuit racing return with the squad this season after a test at the end of 2016.

He was present at the official WEC pre-season test last month but did not drive.

Ahead of the season-opener at Silverstone this weekend, Kubica announced on social media that he would not be racing for ByKolles.

"After the prologue [test], I have decided to interrupt my racing programme with the ByKolles team in LMP1," Kubica said in the statement.

"Therefore, I will not take part in the upcoming WEC Silverstone opening round and in the other WEC races.

"It has been a hard decision to step down and so lose the opportunity to join such a challenging and competitive championship, but I hope this will not be a definitive goodbye."

The ByKolles ENSO CLM P1/01 missed the first two sessions of the Monza test as it was still in the process of being built, and only completed six laps on the Saturday evening - with Oliver Webb driving - before further problems forced the team to abandon the test prematurely.

ByKolles is the sole non-manufacturer LMP1 car entered for this year's WEC season, which commences at Silverstone this weekend with a total of 27 cars on the grid.

Kubica had taken part in several GT events last year as he moved back towards circuit racing having initially returned to competition in rallying - where he won the World Rally Championship's WRC2 title and a European Rally Championship round - following the arm injury that ended his Formula 1 career.

His place alongside Oliver Webb and James Rossiter at ByKolles is set to be taken by Dominik Kraihamer for Silverstone.

Kraihamer, who competed in the WEC for Rebellion Racing last year, had been due to drive on the second day of the Monza test.