Almost three decades after France scrapped conscription, the head of state is due to lay out the change in a speech from 1000 GMT on a visit to an infantry brigade stationed in the Alps in southeastern France, said a presidential official, asking not to be named.

The announcement will come more than three and a half years into Russia's full-scale invasion of Ukraine, with Macron and other French officials warning that Moscow risks not stopping at Ukraine's borders.

France's top general, armed forces chief of staff Fabien Mandon, sparked uproar at home last week by warning that France must be ready "to lose its children", adding that Russia is "preparing for a confrontation by 2030 with our countries".

Macron told the RTL broadcaster he would be announcing a "transformation of national service into a new form" on Thursday but did not provide further details.

A source with knowledge of the matter, who asked not to be named, told AFP that the plan is for 2,000 to 3,000 people to be trained up in the first year, aiming to increase those signing up over time to 50,000 per year.

"It will start slowly," said the source.

This "new form of national service" will be "on a voluntary basis", said a presidential official.

An adviser to Macron, also requesting anonymity, emphasised it would be launched at a time of tight budget constraints. Its implementation will therefore be "phased in over time," said the adviser, promising a "realistic" project that "takes into account our current resources".

- Not going to 'send our young' -

While around a dozen states have some form of conscription, the use of military service is uneven across Europe.

But France would join European countries like Baltic states Latvia and Lithuania which have brought it back in recent years, while others such as Denmark have toughened its terms.

There is so far no suggestion that the military service in France would be compulsory, as it was before then-president Jacques Chirac abolished conscription in 1997 as part of the reform of the army.

Military service is seen as a way of bolstering armies with recruits, but also of providing a large pool of potential reservists, who could be called up in the case of a future war.

The French armed forces have approximately 200,000 active military personnel and 47,000 reservists, numbers expected to increase to 210,000 and 80,000 respectively by 2030.

Accused of warmongering by the left, General Mandon has expressed no regret over his comments last week, saying the aim was to "alert and prepare" amid a "rapidly deteriorating" context.

Mandon argued on Saturday that the reactions to his comments "show that this is something that was perhaps not sufficiently perceived in our population".

But ahead of Thursday's announcement, Macron and other officials have been at pains to douse the outcry caused by the general's forthright comments and fears that French youth were heading for the front lines.

The president on Tuesday said he needed to dispel any notion "we are going to send our young people to Ukraine".

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RTL GROUP