Brussels: The powerful chief of staff to Jean-Claude Juncker, Martin Selmayr, will take a top post in the European Commission in a move announced Wednesday which means he can stay on after his boss steps down next year.

The German — affectionately nicknamed the ‘Monster’ by Juncker and less affectionately dubbed the ‘Rasputin of Brussels’ by the British press — will become secretary general of the commission, the EU’s executive arm.

Selmayr, 47, a lawyer by trade, is already well known as gatekeeper and enforcer to Juncker but has also been involved in controversies including over leaks about Brexit negotiations.

“I am sure that Martin Selmayr will be an excellent secretary general of the commission,” European Commission President Juncker told a press conference as he announced the appointment.

“We need a secretary-general who knows this place and knows Europe so there will be no political rupture.”

Spaniard Clara Martinez will become Juncker’s new chief of staff.

‘We both have enemies’

Former Luxembourg premier Juncker has previously said that he called Selmayr a “monster” because of his capacity for hard work at all hours of the day and night — but the epithet has also been seized on by critics of his take-no-prisoners management style.

Juncker coyly added on Wednesday: “He has one thing in common with me — we both have enemies.”

But he played down reports of tensions between Selmayr and some European Commissioners, saying: “It’s true at times we have difficult relations with different commissioners... it’s perfectly normal.”

Selmayr will replace Alexander Italianer, a Dutch civil servant, who has been secretary-general of the commission since 2015. It is the top civil servant post in the commission, and Selmayr is the first German to get the job.

Despite a reputation as a shadowy power-broker, Selmayr has often been outspoken on social media in defence of his Luxembourgish boss.

Selmayr was the first to break news of a deal between British Prime Minister Theresa May and Juncker in the first phase of Brexit talks in December, when he tweeted a picture of white smoke — a reference to choosing a new pope.

In October he publicly denied leaking details to a German newspaper that reported May had pleaded with Juncker for help in unblocking stalled negotiations.

“I deny that 1/we leaked this; 2/Juncker ever said this; 3/we are punitive on Brexit,” wrote Selmayr. “It’s an attempt to frame EU side and to undermine.”

Pro-European

He has also taken an unashamedly pro-European stance in public comments on political developments in Europe and further afield.

He hailed the election victory of French President Emmanuel Macron last year as a key step in turning back a tide of Euro-scepticism, and railed against US President Donald Trump and other populist politicians.

Juncker’s term of office is due to end in 2019 but the new post means Selmayr will be able to stay on in the commission after that.

There is no time limit on the appointment, with one previous holder staying in the job for 10 years, but Selmayr’s future will depend on who replaces Juncker.

“The next president of the European Commission will decide whether or not to confirm the secretary-general in his position. I don’t want to get involved in this,” Juncker added.

Selmayr is, however, close to EU Brexit negotiator Michel Barnier, the current frontrunner to succeed Juncker.