French President Francois Hollande has named Emmanuel Macron, a former banker and close ally as the new economy minister in an emergency reshuffle after a major political crisis.
Top ministers, including Foreign Minister Laurent Fabius and Finance Minister Michel Sapin, remained in their posts.
However, three rebel ministers who had openly criticised the government's economic policy were not part of the line-up.
The surprise nomination of 36-year-old Mr Macron comes a day after Mr Hollande asked Prime Minister Manuel Valls to form a new cabinet in a shock announcement.
In his first public comments since the reshuffle Mr Valls has said he will hold a parliamentary vote of confidence "in September of in October."
The reshuffle was sparked by a weekend of sniping by outspoken former economy minister Arnaud Montebourg over austerity policies implemented by Paris.
The newly appointed Mr Macron was Mr Hollande's economic advisor until a few months ago.
He pushed the Socialist president towards implementing a more liberal financial policy as the country struggles with stagnant growth and record unemployment.
Mr Macron is very different from his predecessor Mr Montebourg, who is on the left of the Socialist party and advocates cutting taxes and upping government spending.