Caterham-backed Greaves Motorsport has withdrawn from this weekend's round of the European Le Mans Series at Spielberg.
The British squad has been unable to find suitably-funded drivers together with Caterham, which placed GP2 racer Alexander Rossi with the team for last month's Le Mans 24 Hours, to drive its solo Zytek-Nissan Z11SN at round three of the series in Austria.
Team owner Tim Greaves said: "Time has been the issue. Le Mans was very much a late deal and we have been unable to sort out drivers for this weekend."
Greaves is still aiming to contest the final two rounds of the ELMS at the Hungaroring and Paul Ricard in September.
"We do intend to remain in the series and are working hard to find a solution with Caterham, but if that doesn't happen, we will be looking elsewhere to continue on our own," said Greaves.
The withdrawal of the Greaves Zytek means there will be nine LMP2 prototypes present at Spielberg, one down on the 10 that started at Imola in May.
The Murphy Prototypes ORECA squad has confirmed its participation with Brendon Hartley and Swiss Jonathan Hirschi, who is racing for his third different team of the ELMS season.
The Greaves Motorsport has not previously missed an event run to Le Mans rules in Europe since its entry into the prototype arena as Team Bruichladdich at the Nurburgring in July 2006. It has been present at every Le Mans Series, World Endurance Championship and European Le Mans Series event held in Europe since.