To date, this approach hasn’t placated leaders. Ahead of Thursday’s summit, 19 countries were calling for even more deregulation from the Commission. A vocal contingent — including Poland’s Donald Tusk and Italy’s Giorgia Meloni — have made far-reaching demands that the bloc’s existing measures be weakened, in return for even considering supporting the 2040 goal. 

Leaders are not expected to spend much time discussing the actual target, although some countries that are unhappy with the Commission’s proposal — a plan to cut emissions by up to 90 percent below 1990 levels by 2040 — are bound to vent their frustration. 

Costa, who chairs the discussion, has instead asked leaders to discuss how the bloc can marry climate efforts with economic competitiveness. 

Ursula von der Leyen has already spent much of her second term chipping away at green laws she proposed over the previous five years. | Selçuk Acar/Anadolu via Getty Images

Both he and von der Leyen were unwilling to debate the target itself, according to one diplomat from an EU country and a European official briefed on the preparations for Thursday’s summit. 

But his invitation to leaders to outline their conditions for supporting the 2040 target risks “a Christmas tree” effect, the diplomat said, where each leader hitches their own pet policies to the target. 

The diplomat, who was granted anonymity as they were not authorized to discuss the summit, added that French President Emmanuel Macron — who pushed for the leaders’ debate — was seen as pivotal.