BRUSSELS – Under pressure to deliver an updated climate target this month, European Union leaders are unlikely to agree on a more ambitious number when they meet this week if they can't compromise on the 27-nation bloc's long-term budget, top European diplomat says.The last time EU leaders discussed climate targets in October, they could not immediately adopt a proposal requiring unanimous support to cut greenhouse gas emissions by at least 55% by 2030 compared to 1990 levels, and decided to try again during their December summit.But a dispute over the bloc's money has since emerged as Poland and Hungary now threaten to veto a major coronavirus pandemic aid package and the EU's budget for 2021-2027 because of a mechanism linking EU funding.