Building on recent anti-Turkey rhetoric ahead of Germany's federal elections in less than 10 days, Green Party Co-chairman Cem Özdemir said his party would issue a travel warning against Turkey and increase economic pressure.

"If we become the government as of September, a travel warning will be issued," Özdemir said at his party's congress in Berlin on Sunday, Deutsche Welle Turkish reported.

If a travel warning is issued by German authorities, travelers are able to get a refund for the reservations they made in advance.

Known for his stance against Turkey's Justice and Development Party (AK Party) government, Özdemir also vowed to suspend the German government's credits given to investors doing import and export with Turkey.

Berlin-Ankara relations have recently been strained over several issues, the latest of which was the call of German politicians on the EU to end Turkey's accession talks. Both German Chancellor Angela Merkel of the Christian Democrats Union (CDU), as well as her main rival Social Democratic Party of Germany's (SPD) Martin Schulz called for an end to Turkey's EU membership negotiations during a televised political debate in Germany last week. Merkel further promised Tuesday that she would raise the issue of Turkey's membership at an EU leaders' summit in Brussels on Oct. 19-20.