The EU budget, which could reach nearly €2 trillion under the European Commission’s proposal, "must be fundamentally reformed," the letter said. "Unless the budget is cut by hundreds of billions, there won’t be an agreement this year," a diplomat from one of the signatory countries said. The budget requires unanimous approval by all 27 member states, the Financial Times (FT) reported.

The leaders of the six countries believe resources should be redirected toward defense needs and support for innovative companies to address growing economic challenges and security threats, while reducing funding for agriculture and less-developed regions, which traditionally account for about two-thirds of spending under the EU’s financial framework.

The ultimatum highlights disagreements over the EU’s new spending priorities, including defense spending and support for struggling industries amid competition from China and the United States, the report said. The six countries account for about 40% of the bloc’s total budget revenues, which are primarily generated through contributions from member states.

Ireland, which currently holds the EU’s rotating presidency, has been tasked with preparing a compromise proposal by mid-October that could bridge the demands of the largest donor countries with those of the majority of member states seeking to preserve agricultural subsidies and regional development funding, FT reported.