EU leaders have returned to Brussels for a second showdown in two months with Hungary’s Viktor Orbán over his refusal to sanction a new €50bn assistance package for Ukraine.

A mixture of frustration and anger prevailed in the city as leaders arrived for dinner on Wednesday night on the eve of the emergency summit, with aides lamenting the failure of the Hungarian PM to shift position since December, when he first blocked the funds, Ednews reports.

“We are really at a crossroads,” said one EU official.

Diplomats in Brussels stress that Ukraine will not run out of funding for military equipment and ammunition as this comes through individual member states through the European Peace Facility.

Efforts to persuade Orbán to budge have redoubled in the past 24 hours, with representatives of the other 26 EU states agreeing to insert a compromise paragraph in the draft text of the agreement being sought at the summit on the budget.

In recent days Hungary said it would lift its veto but only if the budget was revisited every year of the four-year funding period.

On Wednesday morning member states’ ambassadors proposed an annual debate rather than a vote on the Ukraine fund facility.

The new draft text of the official agreement being sought pledges an annual European Commission review of the implementation of the funds facility.

On that basis “the European Council will hold a debate each year on the implementation of the facility with a view to providing guidance on the EU approach”, the draft text says.

The EU’s chief diplomat, Josep Borrell, said on Wednesday that the EU expected to reach just 52% of its target to send 1m rounds of shells to Ukraine by March this year, according to the latest production data compiled by the commission.