Three weeks after the spectacular jewel theft at the Louvre, the museum has been heavily criticised for neglecting security.

The Court of Auditors report, drawn up before the heist, found that for years managers had preferred to invest in new artworks and exhibitions rather than basic upkeep and protection.

Let no-one be mistaken: the theft of the crown jewels is a resounding wake-up call, said the court's president, Pierre Moscovici.

In broad daylight on Sunday 19 October, thieves broke into the Louvre's first-floor Apollo Gallery. Using a angle-grinder to open display cases, the gang made off with €88m (£78m) of jewels that once belonged to 19th-Century queens and empresses.

Basing its findings on the years 2018 to 2024, the report says the Louvre favoured operations that were visible and attractive at the expense of maintenance and renovation of technical installations, notably in the fields of safety and security.

In the period studied, it found the museum spent €105.4m on buying new artworks and €63.5m on exhibition spaces.

But at the same time it spent only €26.7m on maintenance works and €59.5m on restoration of the palace building.

The findings chime with other criticisms, such as from Culture Minister Rachida Dati who said managers had grossly underestimated the dangers of intrusion into the museum.

One of France's leading art experts, Didier Rykner, has also accused the museum of preferring to spend its abundant resources on eye-catching initiatives rather than basic protection of what it already has.

One possible casualty is the Louvre's ambitious New Renaissance project which was launched with fanfare earlier this year by President Emmanuel Macron and the museum's director, Laurence des Cars.

The plan includes a new entrance at the eastern end of the Louvre, and the excavation of new exhibition spaces including a separate gallery for the Mona Lisa.

But the Court of Auditors found that the project had been undertaken without proper studies - either of technical and architectural feasibility (or)… financial evaluations.

The projected cost had already soared to €1.15bn, it said, compared with the €700m announced in January.

In its response, the Louvre said it accepted most of the court's recommendations, but it believed the court did not fully understand all that it had done – notably in security.

When it comes to the biggest and most visited museum on the world , the only balanced judgment is one that looks at the long term, it said.