EU members are set to boost military budgets by up to 70 billion euros ($72.2 billion) by 2025 but a lack of project cooperation and purchases outside the bloc risk undermining efforts to create coherent forces, the European Defence Agency said.

The agency identified several critical gaps EU countries should work together to fill, such as long-distance air transport, aircraft carriers and tankers to provide fuel for war ships and high-end air defence systems.

"Defence planning continues to be done mostly in isolation and ... (EU) member states remain unconvinced by European cooperation projects," it said on Tuesday in its annual review for the bloc's defence ministers' meeting in Brussels.

EU foreign policy chief Josep Borrell, who doubles as head of the EDA, said defence cooperation coupled with increased spending was the only way to ensure Europe had forces capable of responding to any crisis.

Many countries prefer individual purchases of arms and equipment from suppliers outside the EU rather than investing their money in European projects which are seen as more time-consuming and complex, the EDA said.

The agency said that only 18% of all investment in defence programmes involved cooperation between EU countries.

Defence expenditure in the bloc grew by 6% to 214 billion euros in 2021, the agency said, estimating a further increase of up to 70 billion euros by 2025 as many countries aim to spend more on defence after Russia's invasion of Ukraine in February.

The figures include only part of Germany's pledge to spend an additional 100 billion euros on the Bundeswehr, according to EDA, as it is not clear when the money will flow.

Created in 2004, EDA's main task is to support and facilitate defence cooperation in Europe. ($1 = 0.9696 euros) (Reporting by Sabine Siebold; Editing by Philip Blenkinsop and Alison Williams)