A district chapter of Angela Merkel's Christian Democratic Party (CDU) received €28,000 ($33,114) from the state-run Azerbaijani oil and gas company Socar in contravention of German rules on party donations, a consortium of public broadcasters NDR, WDR and daily Süddeutsche Zeitung reported.

Read more: Azerbaijan laundromat scandal embroils ensnares German MP

The case again calls into question connections between certain conservative politicians and the South Caucasian republic, whose leader, President Ilham Aliyev, has been criticized by human rights organizations.

According to the report, two payments, one of €3,000 and one of €25,000, were deposited by Socar's Germany-based branch on the account of the CDU's district association in Frankfurt at the end of February 2012.

No fine for the CDU

The affair had caused a four-year-long legal dispute with the parliamentary administration authority behind the scenes, the report said, since German law prohibits parties from receiving donations from non-EU countries.

Aliyev: a stranger to democracy

'Azerbaijan Laundromat' scandal ensnares German MP

Although the district CDU branch accepted the donation without question, auditors at party headquarters in Berlin notified the Administration of the German Bundestag, which decided as early as autumn 2013 that the gift was not allowable under the law. The CDU then gave up the donation to be immediately impounded, the report said.

However, despite having broken the law, the party will not have to pay a fine, largely owing to a ruling made by an administrative court in April that self-denunciation in such cases can not only mitigate penalties, but even avert them altogether.

Mysterious links

The affair has raised several questions about links between the conservative CDU/CSU bloc and Azerbaijan, and what objectives the country could be pursuing with its donations.

Listen to audio 05:11 Share Inside Europe:Caviar diplomacy at the Azerbaijani Laundromat Send Facebook google+ Whatsapp Tumblr linkedin stumble Digg reddit Newsvine Permalink https://p.dw.com/p/2jW61 Inside Europe: Caviar diplomacy with the Azerbaijani Laundromat

The German CEO of Socar, Anders Egen Mamedov, was quoted by the paper as saying that the company's contacts with political officials was taking place "against the backbround of the geopolitical importance of Azerbaijan and Socar," including with regard to the pipeline network through seven countries that is currently under construction.

The massive gas pipeline project was chosen over the Nabucco-West pipeline in 2013 with the support of the then EU commissioner for energy, the German CDU politician Günther Oettinger.

Mamedov said Socar also made donations to sports and cultural associations in Germany. He declined to give details or speak about possible donations to other German of European parties to the paper.

Lobbying activities

The Süddeutsche also pointed to CDU parliamentarian Karin Strenz, who according to the paper did not disclose her work for an Azerbaijan-financed lobbying firm within three months as asked. The company is owned by former CSU politician Eduard Lintner, who has been doing lobbying work for Azerbaijan since 2009.

Strenz has a picture of Aliyev on her website

In another possible indication of her sympathies with the authoritarian country, in June 2015 Strenz voted against a resolution by the Council of Europe to call on Azerbaijan to release its political prisoners — the only German MP to do so, according to an earlier report in the paper.

Azerbaijan was described in a resolution by the European Parliament in September 2015 as "having suffered the greatest decline in democratic governance in all of Eurasia over the past 10 years."