The former CDU/CSU parliamentary group leader intensified his criticism of the government's course in migration policy, demanded tax benefits for retirement plans via shares, and said he believed he could get voters back from the anti-immigration Alternative for Germany (AfD) party.

His fiercest competitor, party General Secretary Annegret Kramp-Karrenbauer, known as AKK, highlighted her long government experience as former Saarland state premier as one of the reasons that she is the best choice to lead the centre-right party.

Kramp-Karrenbauer and Merz are the two candidates with the biggest chance of succeeding Angela Merkel, who after 18 years at the top will not run again as party leader. However, she wants to remain Chancellor until her term ends in 2021.

The vote to elect a new chair will take place at the CDU party conference in Hamburg on Friday.

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Union 'shrugged its shoulders' watching AfD rise

On migration policy, Merz said on Saturday at a state party conference of the Saxon CDU in Leipzig that border controls should be introduced.

He said:  “Open borders cannot be an invitation to allow an unregulated influx into the Federal Republic of Germany, over which we have not regained control to this day.

“There are still about 200,000 to 250,000 migrants in Germany whose whereabouts and origins we know nothing about. These are things that we must not allow if we do not want to accept the emergence of extreme political parties,” said Merz, with a nod to the growing strength of the AfD.

The 63-year-old, who has not been in active politics for nine years, has received a lot of opposition within his party for his assertion that the CDU had more or less “shrugged its shoulders” watching the rise of the AfD.

He has been nicknamed the 'anti-Merkel' by the German media because of his completely different political style and attitude to Angela Merkel.

Kramp-Karrenbauer, 56, who is an ally of Merkel, sharply rejected these statements.

At the event in Leipzig she said: “You can argue about many things, whether we did everything right there.” In the past years, however, “countless (party) members” have been involved in the dispute with the AfD. “And they don't deserve to be blamed for not having done enough,” she said.

Annegret Kramp-Karrenbauer, Friedrich Merz and Jens Spahn in Leipzig at the weekend. Photo: DPA

The third promising candidate for the party chairmanship, Health Minister Jens Spahn, demanded that the leaders of the CDU go to the AfD strongholds and seek unbiased discussion. The 38-year-old said there needed to be a programme to win back AfD voters.

Merz reiterated his criticism in an interview with Spiegel: “Parts of the CDU underestimate the political danger posed by the AfD.” It is unacceptable that the AfD should sit in all state parliaments and in the Bundestag with 12.6 percent, he said, adding: “And I dare to change that.”

Merz also underlined his position on another issue: retirement plans.

“We should use the stock markets to create better wealth and capital accumulation in private households in the long term,” the former Union faction leader told the newspaper “Welt am Sonntag”. This would make it easier for many people in Germany to buy their own home.

“I am talking about a supplementary old-age provision that can be added to the statutory pension insurance,” Merz said on the ARD television program “Bericht aus Berlin” (Report from Berlin). There is already a whole range of tax benefits. “I'd like to bundle them, I'd like to concentrate them, I'd like to focus them on pensions.” Merz is Chairman of the supervisory board of Blackrock Deutschland – a branch of the largest asset manager in the world.

SEE ALSO: 'Anti-Merkel' convinced he can take top spot as CDU leadership race heats up

'Profound knowledge

When asked why she thought she was better suited than Merz to be leader, Kramp-Karrenbauer told “Bild am Sonntag”: “I bring in a very profound knowledge of the party, because I have borne responsibility for it for many years”.

She also has experience as an election campaigner: “I know what it's like to be successful as a top candidate even when the wind blows in your face,” she said.

The former state premier was indirectly referring to her success in the state elections in Saarland in March 2017 – despite the fact the SPD was flying high in polls at the time, under its then newly elected candidate for chancellor Martin Schulz, and the internal party dispute within the Union over refugee policy was ongoing.

In February 2018, Kramp-Karrenbauer gave up her post as head of government, which she had held since 2011, to become CDU General Secretary. Merz, on the other hand, has never been a top candidate in an election campaign.

In the interview, Kramp-Karrenbauer also revealed her human side. AKK said she had been a good pupil at school and didn’t have much time for rebellion. “I was more of a nerd, although I didn't always get top marks,” she said. She never “blau gemacht” – which means she didn’t skip school – and didn’t smoke either.

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