Ukraine will receive up to 100 of France's Rafale F4 fighter jets as well as advanced air defence systems in a major deal to boost Kyiv's ability to protect itself against deadly Russian attacks.

Ukrainian President Volodymyr Zelensky hailed the move as historic, after signing the letter of intent with his French counterpart Emmanuel Macron at an air base near Paris.

Deliveries of the Rafale F4s are planned to be completed by 2035, while the joint production of interceptor drones is starting this year.

Financial details are yet to be worked out, but reports say France plans to attract EU financing and also access frozen Russian assets - a controversial move that has split the 27-member bloc.

This is a strategic agreement which will last for 10 years starting from the next year, Zelensky said at a joint briefing with Macron on Monday.

Ukraine will also get very strong French radars, eight air defence systems and other advanced weaponry, he added.

Zelensky stressed that using such advanced systems means protecting someone's life... this is very important.

Russia has in recent months increased its drone and missile attacks on Ukraine, targeting energy and rail infrastructure and causing massive blackouts across the country. Dozens of civilians have been killed in the strikes, in what Kyiv and its Western allies describe as war crimes. In the latest overnight Russian missile attack, three people were killed and 15 injured in the north-eastern city of Balakliya, local officials said.

Speaking alongside Zelensky, Macron said: We're planning Rafales, 100 Rafales - that's huge. That's what's needed for the regeneration of the Ukrainian military.

These fighter jets are seen as crucial to protecting Ukraine's skies, because the country is almost powerless in preventing long-range air strikes on its border towns and cities.

While this announcement between Kyiv and Paris is sizeable, Justin Bronk from the Royal United Services Institute (Rusi) pointed out: The difference they'll make will depend on the timeframe and the missiles that come with them.

This is a long-term political agreement rather than a detailed purchase order, so few are expecting this announcement to dramatically change the dynamics of Russia's grinding invasion.

With the Rafales, further complexities arise around the question of who pays. It's thought France will dip into its own budget contributions for Kyiv, as well as look at joint EU borrowing mechanisms to help pay for the deal.

After France, Zelensky will travel to Spain to seek further military and other support for Ukraine. Over the weekend, he secured a gas deal with Greece. Vital supplies of US liquefied natural gas are now expected to start flowing into Ukraine this winter via a pipeline across the Balkans.

Russian President Vladimir Putin launched a full-scale invasion of Ukraine in February 2022. Moscow currently controls about 20% of Ukraine's territory. Russian troops have been making slow advances along the vast front line - despite reported huge combat casualties.