Kubica calls off LMP1 WEC programme

Robert Kubica has cancelled his 2017 World Endurance Racing programme with the LMP1 ByKolles outfit.

The former F1 driver had been scheduled to return full-time to circuit racing this season with the private WEC team following a test at the end of last year.

Just days before the series gets underway at Silverstone, Kubica had a change of heart, announcing on social media that he would not be racing with 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 to lose the opportunity to join such a challenging and competitive championship, but I hope this will not be a definitive goodbye."

Kubica confesses that 'F1 period is gone'

The details of Kubica's decision are not known but ByKolles endured a difficult time at the WEC prologue test in Monza recently.

Its ENSO CLM P1/01 missing the first two sessions and only completing six laps on the Saturday evening - with Oliver Webb driving - before problems halted the team's test.

GALLERY: F1 drivers' wives and girlfriends

Keep up to date with all the F1 news via Facebook and Twitter

Phillip van Osten

Motor racing was a backdrop from the outset in Phillip van Osten's life. Born in Southern California, Phillip grew up with the sights and sounds of fast cars thanks to his father, Dick van Osten, an editor and writer for Auto Speed and Sport and Motor Trend. Phillip's passion for racing grew even more when his family moved to Europe and he became acquainted with the extraordinary world of Grand Prix racing. He was an early contributor to the monthly French F1i Magazine, often providing a historic or business perspective on Formula 1's affairs. In 2012, he co-authored along with fellow journalist Pierre Van Vliet the English-language adaptation of a limited edition book devoted to the great Belgian driver Jacky Ickx. He also authored "The American Legacy in Formula 1", a book which recounts the trials and tribulations of American drivers in Grand Prix racing. Phillip is also a commentator for Belgian broadcaster Be.TV for the US Indycar series.