A European air force of 120 fighter jets could be deployed to secure the skies from Russian attacks on Kyiv and western Ukraine without necessarily provoking a wider conflict with Moscow, according to a plan drawn up by military experts.

Sky Shield, its proponents argue, would be a European-led air protection zone operated separately from Nato to halt Russian cruise missile and drone attacks on cities and infrastructure, potentially operating as part of the “truce in the sky” proposed by Ukraine’s president, Volodymyr Zelenskyy, this week.

It would cover Ukraine’s three operating nuclear power plants and the cities of Odesa and Lviv, but not the frontline or the east of the country – and, according to a newly published paper, it could “achieve greater military, political, and socioeconomic impact than 10,000 European ground troops”.

Supporters include Philip Breedlove, a former US Air Force general and Nato supreme commander in Europe, and Sir Richard Shirreff, a former British army general and deputy Nato supreme commander at the beginning of the last decade, as well as former Polish president Aleksander Kwaśniewski.

Another backer, Gabrielius Landsbergis, a former Lithuanian foreign minister, said in a statement: “The implementation of Sky Shield would be an important component of Europe’s stepping up, guaranteeing Ukraine’s security effectively and efficiently.”

Though variants of the proposal have been discussed without making progress since Russia launched the full-scale invasion of Ukraine in February 2022, a fresh version of the plan has gained renewed impetus this week after Zelenskyy’s acrimonious meeting with US president Donald Trump on Friday.

Since then the US has halted military aid and curbed intelligence sharing with Kyiv, prompting a rapid realisation in Europe that the continent will have to take the lead in supporting Ukraine while the war continues and by providing security guarantees to the country as part of any peace deal.

It is understood Sky Shield has been drawn up by former RAF planners working in conjunction with Ukraine’s armed forces, and it has been canvassed before European defence ministries. However, there has been no real appetite from European leaders to sanction patrols of Ukrainian skies while the war is ongoing.

Those involved believe the pace of events in the last week means that ideas about protecting some of Ukraine’s airspace can now get a fresh hearing, though the plan also serves to highlight how important and efficient air protection would be as part of providing security guarantees to Kyiv in the event of a ceasefire.

The concern in western political circles is that it would risk placing fighter jets from Nato member states directly in conflict with Russia, and could lead to a dangerous escalation of hostilities if a jet from either side was attacked or shot down.

However, backers of the scheme argue the “risk to Sky Shield pilots is low” because Moscow has not dared to fly its combat jets beyond the existing front lines since early 2022. The de facto separation from Russian aircraft would be “more than 200km” according to the scheme’s designers.

Russia routinely attacks Ukraine with missiles and long range drones and the belief is that fighter patrols could help Kyiv eliminate them. Knocking them out is a burden on Kyiv’s existing air defence, some of which – most notably Patriot interceptors – are manufactured in the US and whose resupply is covered by the White House ban.

On Wednesday, Ukraine’s military said 181 drones and four missiles had been launched by Russia. Though most of the drones were shot down, one person was killed in the southern city of Odesa and infrastructure was targeted in the region, the local authorities said.

Ukraine has fewer missiles than Russia but has used US Atacms and Anglo-French Storm Shadow missiles to strike targets inside Russia since the autumn. It has also conducted a string of long range drone attacks on military and other infrastructure, such as refineries.