EU foreign policy chief Josep Borrell says the European Union has provided Ukraine with more than 980,000 artillery shells, and will soon reach the promised 1 million mark.

EU leaders agreed at a summit last year to supply Ukraine with 1 million rounds of ammunition by March 2024.

In an interview published in Ukrainian media on Monday, Borrell said delivery is behind schedule because, "We didn't know exactly what our production capacity was" when they made the pledge.

But he said the EU has increased production capacity by more than 40 percent. He suggested that if a Czech-led initiative and other efforts are combined, more than 1.5 million shells will be supplied by the end of the year.

In March, CNN reported that Russia's artillery production capacity is much higher than that of the United States and Europe.

The US broadcaster said NATO estimates and other sources, including a European intelligence official, indicate that the US and Europe have an annual capacity of about 1.2 million shells compared to Russia's 3 million.