Leaders from more than 25 countries will meet in Paris to secure additional air defence systems and interceptor missiles as Ukraine faces growing shortages and intensified Russian missile attacks.
The coalition is also expected to discuss fresh sanctions on Russia.
Other topics include joint weapons production, and preparations for a future multinational force to support Ukraine after any peace agreement.
Leaders of more than 25 countries will meet in Paris on Monday to secure additional air defence support for Ukraine, as Russian missile strikes intensify and Kyiv warns that shortages of interceptors are leaving its cities increasingly vulnerable.
Ukrainian President Volodymyr Zelenskyy will join leaders from at least 25 countries at a meeting of the Coalition of the Willing, where discussions will focus on strengthening Ukraine's air defences, coordinating a common negotiating position towards Russia and developing security guarantees for any future peace agreement.
The meeting comes days after the NATO summit, which sought to demonstrate long-term transatlantic support for Ukraine.
Russia has intensified missile and drone attacks on Kyiv and surrounding regions in recent weeks, killing dozens of people. Ukrainian officials said Russian strikes across the country on Saturday killed at least eight people and wounded many more.
"Today, the Russians have once again 'triumphed' over absolutely civilian targets," Zelenskyy said in a social media post after fresh attacks on Monday.
"The pressure on Russia must work. New sanctions against the aggressor. New packages of support for Ukraine, new projects-like our European anti-ballistic project FREYJA- everything must work."
Russia says it targets only military-related sites and denies deliberately attacking civilians.
A French presidency official said the summit would focus on expanding cooperation on ballistic missile defence, including securing additional U.S.-made Patriot interceptors, accelerating deployment of the Franco-Italian SAMP-T air defence system, and developing European alternatives through closer cooperation between European and Ukrainian defence industries.
Ahead of the summit, representatives from nine countries are due to meet with about a dozen defence companies, including Eurosam, Leonardo, Thales and Saab, to discuss increasing air defence production, diplomats said.
Diplomats said leaders were also expected to announce the formal launch of the FREYJA project, Ukraine's initiative to develop a European-backed, lower-cost alternative to the Patriot missile defence system.
Ukraine has warned that it is critically short of interceptor missiles and has struggled in recent weeks to shoot down Russian ballistic missiles, which travel several times faster than the speed of sound.
"The ballistic missiles launched by (Russian President) Vladimir Putin are deliberately targeting civilian zones and June was one of the most murderous (months) since the start of the war," French Foreign Minister Jean-Noel Barrot said in an interview with Ouest-France on Sunday.
Leaders are also expected to discuss measures to curb Russia's revenues, particularly by targeting its so-called "shadow fleet" of oil tankers used to circumvent Western sanctions.
The European Union is expected to approve its 21st package of sanctions against Russia next week.
Macron has said Monday's summit will include several announcements, some on bilateral defence cooperation, including potential joint weapons production.
The coalition is also expected to discuss joint military exercises as part of preparations for a future multinational force to support Ukraine after any peace agreement.
"What must be remembered is that the MNFU consists of land, air, sea and training. All of these pillars are intended to be tested continuously, to varying degrees, with all participants in order to guarantee their credibility," the French presidency official said.
"It's not a question of conducting exercises in Ukraine."
(inputs form Reuters)
