Chancellor Angela Merkel said on Monday that Germany will likely miss the government's target of bringing 1 million electric cars onto the roads by the end of the decade.
In return, Mr Macron said that he would work with Ms Merkel on a "road map" and that they needed to work on "deep reforms that are necessary and need common work".
But both leaders said they could tackle treaty change. Germany, which has Europe's largest economy, has always opposed taking direct responsibility for weaker European Union countries' debts.
The meeting's warm tone reflected rising hopes in Germany that Mr. Macron may be able to deliver what officials in Berlin have long demanded: a convincing overhaul of France's tightly regulated economy that would jump-start growth in the eurozone's second-largest economy.
The German leader also said that she and Macron have an interest in moving forward with the establishment of a common asylum system within the EU and on the Defence Union. That gave the party, with which Merkel governed Germany from 2009 to 2013, a strong base for its drive to return to the national parliament in September after it was ejected four years ago. "So I believe we are at a very sensitive moment in history that we should now also take advantage of - to make something of it that will be understood by the people as a strengthening of Europe".
And, despite the smiles on Monday, Mr Macron has yet to prove himself. Macron made clear his vigor for European Union reform was no empty campaign promise.
Taking over from outgoing prime minister Bernard Cazeneuve during a short ceremony, Philippe described himself as "a man of the right" who was driven by "the greater good". It would be managed by a newly created joint finance minister for the eurozone.
Macron has shaken up French politics with his meteoric rise to the presidency.
Indeed, Macron, a former investment banker, will be counting on winning votes for his party from center-right supporters in that round of elections.
Some in the party have argued in favour of an alliance with Macron.
But not everyone was pleased with the Philippe announcement.
In Berlin, the 39-year-old French leader urged a "historic reconstruction" of Europe to battle populism sweeping the continent, following his defeat of far-right leader Marine Le Pen.
Macron's party Le Republique en Marche has unveiled more than 400 candidates for June's elections. His appointment as premier is a blow to the Republicans, who have been trying to regroup after the presidential vote and prevent defections to Macron's camp.
"I don't underestimate the difficulty that implies", Mr. Macron said.
The German Chancellor called Macron's visit a sign of deep friendship between the two main drivers of European integration and the bloc's leading economies.
Germany is looking to Mr Macron to revitalise France as an economic power and political heavyweight in the European Union, which is facing complex divorce proceedings with its current number two economy, Britain.
"On the other hand, Macron's style suits the chancellor".