France is to step up efforts to instil moral values in the global market economy by urging policymakers to consider fresh ways of combating financial short-termism.

Nicolas Sarkozy, France’s president, and Tony Blair, the former UK prime minister, will jointly host a conference in Paris next week of political leaders and Nobel prize-winning economists to discuss ways of strengthening the ethical foundations of the capitalist system after the financial crisis.

“There is no system of wealth creation without a system of values and this value system has been badly shaken,” said Eric Besson, the French minister for policy planning, who is organising the conference.

“People are prepared to accept others getting high pay and enjoying different lifestyles, but only if they have the feeling that the system is fair and that the law is the same for everybody.”

Mr Besson criticised complex securitisation of debt, excessive financial leverage, short-selling and demands for unrealistic returns on investment, saying they pointed to a pervasive “failure to value the long term” across all sectors of the economy for the past 20 years. “Nobody wants to ban the stock market,” he said, even though it had become a “casino”.

“But how can we return to certain fundamental values where the stock exchange is the place businesses come to for the long-term capital they need?”

Mr Besson, a former Socialist party adviser who jumped ship to Mr Sarkozy’s centre-right government, acknowledged that it was more difficult to find the technical solutions than diagnose the problems.

But he said this should not prevent a long overdue discussion by top policymakers, economists and intellectuals on how to restore a sense of responsibility to the global financial system.

“Those who want to defend the virtues of free market capitalism must at the same time demand a balance of rights and responsibilities from top executives. Setting an example matters.”

An “intellectual opening- up” in the wake of the financial crisis, a new US administration and a second summit of G20 leading and emerging economies in April made it the right moment to discuss the values underpinning capitalism before moving on to specific regulatory issues.

“I think the accession of Barack Obama is going to create an extraordinary window of opportunity,” he said. “From what I have heard, he talks the language of regulation.”

But Mr Besson added there would be many people, for now keeping quiet, who would argue that the financial crisis was a “little car accident” caused by a few specific US problems and that it would soon be “back to business as usual”.

Mr Sarkozy has long argued for the “moralisation” of capital, calling for a capitalism for entrepreneurs rather than speculators.

He was instrumental in bringing about the first summit of G20 in Washington in November but has so far come up with few detailed policy proposals of his own.

Mr Besson dismissed suggestions that the conference was an attempt by Mr Sarkozy to hog the limelight and control the policymaking agenda ahead of the G20 summit with another international gathering in Paris.

“The idea of regulation automatically sounds better to French ears whatever their political convictions,” Mr Besson said. But France’s instincts would be tempered by the need to keep on board other European capitals, particularly London and Berlin, he said.