BERLIN, Sept. 14 (Xinhua) -- German foreign minister Heiko Maas told press on Friday that he will appeal to his Russian counterpart Sergey Lavrov to prevent a major offensive of Syrian government against the rebel-held Idlib region.

"We all know what is at stake. We must prevent the worst possible outcome, namely a new humanitarian catastrophe," Maas said ahead of a meeting with Lavrov in Berlin.

The northern Syrian Idlib region on the border with Turkey is the last stronghold of Islamist rebels in the country. Maas warned on Friday, however, that an action against the militants did not justify putting the lives of three million inhabitants at risk who are currently caught in the cross fire.

Earlier, German chancellor Angela Merkel said that it was "naturally right to fight these radical forces" while urging the Syrian government to ensure that civilians were protected.

International aid groups have highlighted that a major offensive is likely to lead to chaos in the Idlib region and attempts by hundreds of thousands of refugees to escape the conflict by fleeing over the border to Turkey.

Maas emphasized that Germany was only willing to heed Russian calls to support the reconstruction of Syria as long as certain conditions were met to ensure long-run stability and peace in the war-torn country.

"As long as there is a political solution in Syria which leads to free elections, we are ready to take responsibility during the reconstruction effort," the minister said.

Lavrov is currently visiting the German capital to mark the ceremonial conclusion of a year-long initiative to forge partnerships between cities in Russia and Germany. Additionally, both foreign ministers have announced plans to take first steps towards closer cooperation in the fields of higher education and research on Friday.