Upon being sworn in, Castex said that he was taking over the leadership of the French government during a difficult period in which priorities and methods will have to be adapted.
More than ever, we will need to bring the nation together to fight the crisis that is taking hold, he said.
Castexs appointment came hours after Macron dropped centre-right premier, Edouard Philippe, and his government.
It is common practice for a French president to replace a prime minister during the five-year presidential term.
The centrist presidents move came despite opinion polls showing that Philippe has gained public support during the coronavirus crisis and is now considerably more popular than Macron.
A survey by polling firm Elabe for BFMTV television, published on Wednesday, showed that 57 per cent of respondents wanted Philippe to stay on.
Even before the epidemic hit, the president was polling poorly.
His administration has been buffeted by huge protests for more than a year, first by the Yellow Vests movement and then by trade unions opposed to planned pension reform.
There has been speculation that Macron could seek a more social orientation to compensate for the perception that his government has been strongly pro-business.
Sundays municipal elections, which saw Green mayors take power in six new major cities while Macrons centrist party flopped, may also influence the new government line-up.
The president told French regional newspapers, in an interview published late Thursday, that there would be only a few priorities for the coming period.
He cited restarting the economy in the first place, along with reconstructing Frances social and environmental protection systems, re-establishing a fair republican order, and defending European sovereignty.
Yes, there is always a need for new faces, for new talent, the president said.
In an address to the nation two weeks ago, Macron promised to reinvent himself after the coronavirus crisis.
He said he would set out a new path in another speech in July.
In the interview, Macron said he would be going ahead with a controversial pension reform that should see Frances multiple systems merged into a single national pension scheme.
But he said he was not opposed to the reform being transformed. (dpa/NAN)
Source: NAN News