Kramp-Karrenbauer was elected as the head of Christian Democratic Party (CDU) in December 2018 after Merkel announced to step down as party chief.
Annegret Kramp-Karrenbauer, who is in the pole position to succeed Angela Merkel as chancellor threatened to step down if the party doesn't back her, forcing the party to back her and pledge her loyalty.
"If you are of the view that the Germany I want is not the Germany you imagine, if you are of the view that the way I want to go with you is not the way you think is the right one, then let's speak today and let's end it today, here, now, said Kramp-Karrenbauer to delegates in a conference speech, responding to the criticism of her leadership.
Kramp-Karrenbauer was elected as the head of Christian Democratic Party (CDU) in December 2018 after Merkel announced to step down as party chief. However, Kramp-Karrenbauer has been in the middle of many controversies that have severely dented her popularity and raised questions of her suitability once Merkel leaves office as German chancellor.
"But, dear friends, if you want this Germany, if you want to take this path together ... then let's roll up our sleeves here and now and make a start," she added before delegates gave her a seven-minute standing ovation to support her.
The meeting was held under the banner of "Germany's strong middle" as the CDU aimed to regain its position where Greens have surged.
So far, the performance of Merkel's would-be successor has been under-par as the party suffered losses in the election to the European Parliament in May and setbacks in regional polls. An INSA poll on Monday predicted that CDU's popularity is down to 25 per cent from 32.9 per cent support it received in the 2017 federal election.
"It isn't and it hasn't been an easy year," she said.
Recent surveys indicate that Germans prefer Merz when it comes to who should succeed Merkel as chancellor at the next elections.
Kramp-Karrenbauer also in a veiled attack targetted 64-year-old lawyer Friedrich Merz, who narrowly lost to her in last year's leadership vote. "To stand here as a party and say that everything we have done in the last 14 years was wrong is not a good election strategy," she warned.
Merz, who narrowly lost out to Kramp-Karrenbauer in last year's leadership vote, grabbed headlines recently when she described the performance of CDU-led government as "abysmal" and accused Merkel of poor leadership.
"They were and are 14 good years for Germany and we can all be proud of that," Kramp-Karrenbauer said in her speech.