German Foreign Minister Annalena Baerbock on Wednesday named former Greenpeace chief Jennifer Morgan as her special climate envoy, as part of a pledge to put the battle against global warming "at the top" of the diplomatic agenda.

US-born Morgan, 55, co-leader of Greenpeace International since 2016, will be the first person to hold the newly created role in Europe's top economy. 

The eye-catching appointment comes as Germany's two-month-old coalition government, led by Social Democrat Chancellor Olaf Scholz, aims to pursue more global cooperation against climate change.

Baerbock, from the ecologist Green party, introduced Morgan as "the face of Germany's international climate policy".

"Even in our foreign policy we are putting the climate crisis where it belongs: at the top of the agenda," Baerbock told reporters after Scholz's cabinet approved Morgan's appointment.

The appointment caused a stir in Germany, with supporters hailing it as a coup for Baerbock while critics accused the minister of blurring the line between lobbying and governing.

Morgan's US nationality also drew scrutiny, which Baerbock countered by saying Morgan was in the process of applying for German citizenship and that it suited the foreign ministry to have international staff in a "globalised world".

The new role will see Morgan work as a special representative for international climate policy initially and as state secretary in the foreign ministry once she has acquired German citizenship.

Morgan said "time is running out" to limit global warming to 1.5 degrees Celsius, requiring "international cooperation like we have never seen before".

After 30 years of environmental activism, Morgan said she felt she "can now make the biggest difference" in Germany's foreign ministry.

"The effects of the climate crisis can already be felt worldwide. People and nature are suffering," she said alongside Baerbock in Berlin.

Scholz has pledged to use Germany's G7 presidency this year to create a "climate club" of leading economies, with the goal of agreeing common climate protection standards and avoid competitive disadvantages as countries transform their economies to reach carbon neutrality.

Karsten Smid, a climate and energy campaigner for Greenpeace in Germany, congratulated Morgan on Twitter. "We will miss you," he said. 

Thomas Silberhorn, a lawmaker from the opposition CSU conservative party, condemned the appointment.

"The government apparently has a problem differentiating between government, activists and lobbyists," he told German media.