"The first of these aircraft have arrived in Ukraine today," Lecornu said on X, without saying how many had been delivered.

After France helped train Ukrainian pilots over recent months, "they will now help defend Ukraine's skies", he added.

Ukrainian leader Volodymyr Zelensky hailed the delivery, which comes amid fears of decreasing support from Washington since US President Donald Trump's inauguration.

"France's president (Emmanuel Macron) keeps his word and we appreciate it. This is another step in strengthening Ukraine's security," he said.

In June, Macron announced that France would transfer Mirage 2000-5 aircraft to Ukraine and train their Ukrainian pilots as part of military cooperation with Kyiv.

Of the 26 Mirage 2000-5 aircraft owned by the French air force, six were to be transferred to Ukraine, according to a budget report published by France's lower house of parliament.

The French defence ministry neither denied nor confirmed the figure for security reasons.

Ukrainian pilots and mechanics have been trained in eastern France to use the jets, which have undergone modifications including to combat Russian jamming.

France announced the delivery of the first fighter jets at a time when talk of a negotiated end to the nearly three-year war has increased -- with Donald Trump back in the White House and Ukraine's troops struggling on the battlefield in the east.

In August, Ukraine received its first consignment of US-made F-16 fighter jets.