The centrist party of French President Emmanuel Macron looks on course to win a landslide victory following the first round of parliamentary elections.

Projections show La République en Marche (Republic on the Move) and its MoDem ally set to win up to 445 seats in the 577-seat National Assembly.

The Socialists, France’s former ruling party, are seen losing 200 seats.

Traditional parties are urging voters to back Mr Macron’s rivals in a run-off vote to avoid him monopolising power.

Mr Macron’s party was established just over a year ago and many candidates have little or no political experience.

The final outcome will be decided in the second round of voting next Sunday.

With all the ballots counted, Mr Macron’s LREM and MoDem won 32.3% of the vote.

The centre-right Republicans had 21.5%, while the far-right National Front (FN) had 13.2%, followed by the far-left La France Insoumise (France Unbowed) on just over 11%.

The Socialists, previously France’s ruling party, and their allies won just 9.5%.

But turnout was sharply down, at 48.7% compared with 57.2% in the first round in 2012, which analysts said reflected a sense of resignation among Mr Macron’s opponents.

Only four seats were settled in the first round. In the run-off vote, the other seats will be disputed by the two top-placed contenders and any other candidate who won the support of at least 12.5% of registered voters in the district.

Composite picture of retired bullfighter Marie Sara; Rwandan refugee Hervé Berville and mathematician Cédric Villani

Those include LREM candidates Marie Sara, a retired bullfighter who will compete against FN stalwart Gilbert Collard in Arles; a Rwandan refugee in Brittany, Hervé Berville, who will face the Republican Didier Déru; and Cédric Villani, a “mathematics evangelist” known for his unique dress sense – including large spider brooches – who will fight against the Republican Laure Darcos.

Manuel Valls, the unpopular Socialist ex-prime minister who was rejected as a candidate by both LREM and the Socialists, will face Farida Amrani, from the far-left France Unbowed, in Essonne.

The election took place amid heightened security after a series of devastating terror attacks in recent years.

There can be no disputing the extraordinary achievement of Emmanuel Macron. Yes, he has certainly had luck but he has also foreseen with uncanny clarity how – with the right moves at the right places at the right times – the map of French politics was waiting to be redrawn.

If the projections from the first round are sustained, then the change that is about to happen to the National Assembly is as big as the one that occurred in 1958 when Charles de Gaulle brought in the Fifth Republic.

Scores, hundreds, of new MPs will be arriving who have never set foot in a debating chamber of any kind, let alone the country’s legislature.

It is all liable to bring a rush of blood to the head, and the greatest danger right now for Macron and En Marche is hubris. The victory is no doubt spectacular but so far it has all been electoral.

Phase two of the Macron master plan – actual reform – is the next challenge. And bigger.

Mr Macron, 39, defeated Marine Le Pen in the presidential run-off last month.

He needs a majority to push through the changes that he promised in his campaign, which include:

  • Budget savings of €60bn (£51bn; $65bn) in the next five years
  • Cutting the number of public servants by 120,000
  • Reforming the labour market and generous state pension schemes, bringing them into line with private schemes

He has already left an impression around the world, in particular for standing up to US President Donald Trump on issues like climate change.

After the projections were announced, a government spokesman said voters had shown they wanted to move fast on major reforms.

François Baroin, head of the Republicans, said the low turnout testified to the “deep divisions in French society” and was “extremely worrying”.

FN leader Marine Le Pen blamed her party’s poor performance on the low turnout, saying France’s electoral system, which favours larger parties, needed to be reformed.

“This catastrophic abstention rate should raise the question of the voting rules which keep millions of our compatriots away from the polling stations,” she said.

Socialist leader Jean-Christophe Cambadélis, who lost his seat in the first round, warned voters against giving LREM an absolute majority next Sunday.

He said it would result in “virtually no real opposition and we will have a National Assembly without any real counterbalance, without a democratic debate and not worthy of that name”.

Elsewhere, German Chancellor Angela Merkel – who, like Mr Macron, has a pro-EU stance – congratulated him on the “great success” of his party. It was a “vote for reforms”, tweeted (in German) her spokesman, Steffen Seibert.