Germany's vice chancellor Sigmar Gabriel | Louisa Gouliamaki/AFP via Getty Images Sigmar Gabriel: Europe will not be blackmailed by Turkey German vice chancellor says Turkey is ‘drastically’ distancing itself from Europe.

Germany and the European Union "should under no circumstances be blackmailed" by Turkey during talks on visa liberalization for Turkish citizens, German Vice Chancellor Sigmar Gabriel said Monday.

"It is up to Turkey if there is or there isn't visa liberalization," Gabriel said during a trip to northern Germany, according to German media.

Visa liberalization was one of the incentives offered to Ankara by the EU in exchange for help tackling the migration crisis. Turkey was also given money and told that its dormant EU membership bid would be restarted.

Gabriel's remarks came after Turkish Foreign Minister Mevlüt Çavuşoğlu warned that Ankara would no longer support the EU-Turkey migration deal if Turkish citizens do not receive visa-free travel by October at the latest.

Gabriel, who leads the Social Democrats, the junior partner in the coalition government, also commented on the recent coup attempt in Turkey and the government's subsequent crackdown against those it feels were responsible. He said: "A country that is on its way to reintroduce the death penalty distances itself so drastically from Europe that naturally all negotiations eventually become superfluous."

Tensions between the two countries have continued to rise in recent days. On Monday, Turkey summoned a senior German diplomat to discuss the fallout from a rally on Sunday in which tens of thousands of Turks took to the streets of Cologne in support of Turkish President Recep Tayyip Erdoğan.

A German court ruled that Erdoğan could not address the rally via a videolink, a decision that angered Ankara.

"The decision not to allow the broadcast was absolutely fine and also lawful," Gabriel said Monday.