Ukrainian leaders have made urgent calls for more help from the West as an intense “artillery war” with Russian forces in the country’s east saps ammunition and weapons stocks.

“Everything now depends on what [the West] gives us,” Vadym Skibitsky, deputy head of Ukraine’s minister intelligence, said in an interview with Britain’s Guardian newspaper Friday.

The pleas come during a fierce battle centered on the strategic city of Severodonetsk, which is largely controlled by Russian forces. The Ukrainian Defense Ministry’s Main Intelligence Directorate said Friday that despite Russia’s superior firepower, the war’s grinding pace could mean another year of fighting.

A prolonged war could jeopardize Ukraine’s bid to join the European Union and other Western institutions. Ahead of an E.U. summit this month, diplomats said it was not yet clear if the 27-member bloc would agree to grant Ukraine “candidate status,” an early step on the long path to membership.