Henrik Enderlein, of Germany's Hertie School of Governance, and Jean Pisani-Ferry, head of the France Strategie government think-tank, offered an implicit trade-off between shaking up the rigid French labour market and regulated professions, and a public investment boost in creaking German infrastructure.
"The biggest danger we see right now is a period of window dressing where lip service is paid to grand projects and reforms, but no real steps are taken," they said, noting both countries face elections in 2017 and there was no time to lose.
"Europe cannot afford to disappoint again, neither economically nor politically," they said.
The reform proposals for France broadly mirrored measures Economics Minister Emmanuel Macron has outlined to ease constraints on employment and open sectors to more competition without embracing more radical ideas such as scrapping the 35-hour work week or cutting unemployment benefits.
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However, although Macron and his German counterpart Sigmar Gabriel commissioned the report, the French ministry distanced itself in advance from the findings, stressing it was not a government reform plan and the proposals were not binding.
The report called for French wage negotiations to cover a three-year period, as in Germany, rather than being annual; for companies in difficulty to have more scope to negotiate with unions on short-time working, pay and jobs; and to make the cost of layoffs more predictable and remove legal delays.
It said the unemployment insurance system was not working but it did not propose specific changes. It also said France should aim to bring public spending below 50 percent of gross domestic product from 56.5 percent in 2014, but set no deadline.
It recommended linking increases in France's minimum wage to productivity gains instead of the average wage rise.