Ukraine war live updates: NATO chief floats 100 billion euro fund for Kyiv; Ukraine shoots down 4 Russian drones overnight

This is CNBC's live blog tracking developments on the war in Ukraine. See below for the latest updates. 

NATO foreign ministers are gathering in Brussels, where the alliance's Secretary-General Jens Stoltenberg is proposing a five-year, 100 billion euro ($107 billion) military and fund for Ukraine. It is not yet clear where the money would come from.

The U.K.'s Foreign Minister David Cameron meanwhile is urging member states to invest more in defense and increase industrial production, saying it is necessary if the alliance wants Ukraine to defeat Russia.

Elsewhere, Ukraine's air defenses shot down four Iranian-made Shahen drones fired from Russia overnight, its air force said in a statement.

Ukrainian air defenses shot down four Russian drones overnight in the eastern Donetsk region, the country's military said.

"On the night of April 3, 2024, the enemy attacked the Donetsk region with three S-300 anti-aircraft guided missiles and launched 4 Shahed-136/131 UAVs from the Primorsko-Akhtarsk area of the Russian Federation," Ukrainian state news outlet Ukrinform quoted the country's air force as saying in a statement.

"Mobile fire groups" intercepted the Iranian-made Shahed drones in the regions of Khmelnytskyi, Zhytomyr, Kirovohrad, and Cherkasy, the statement added.

— Natasha Turak

NATO Secretary-General Jens Stoltenberg on Wednesday will reportedly propose a 100 billion euro ($107 billion) military aid fund for Ukraine, the duration of which would be five years.

The package would allow the transatlantic alliance to aid Ukraine more directly, Reuters reported, citing five unnamed diplomats.

— Natasha Turak

Ukrainian President Volodymyr Zelenskiy has signed a bill to cut the mobilisation age for combat duty to 25