Germany is looking at buying four additional Patriot missile-defense systems at a cost of as much as €1.2 billion ($1.3 billion) on top of the four Chancellor Olaf Scholz’s government ordered in March.

The plans are at an early stage and officials are still assessing how to finance the expanded order, which could lift the overall price tag to about €2.6 billion, according to people familiar with the plans, who asked not to be identified discussing confidential information.

A spokesman for the defense ministry in Berlin declined to comment on specific procurement projects, referring instead in general terms to the government’s push to better equip the armed forces.

Scholz on Thursday urged fellow European Union leaders to send Ukraine more Patriot units - which are manufactured by US defense contractor RTX Corp. - as Russia escalates missile and drone strikes on energy infrastructure and urban centers. His ruling coalition announced last weekend that it will send a third Patriot to the government in Kyiv together with other air-defense systems.

The budget committee in the lower house of parliament in Berlin in March approved the procurement of the initial four Patriots, with the first one expected to be delivered by the end of next year.

That followed a decision in December backing the purchase of 500 guided missiles with spare parts in an order worth a total of around €3 billion.

An abbreviation for Phased Array Tracking Radar to Intercept on Target, Patriot is designed to provide protection against hostile aircraft and missiles and is used by 19 governments including the US, according to RTX.

Germany’s Bundeswehr armed forces plan to keep it as their most important system for ground-based air defense until well beyond 2030.