Rapprochement between Turkey and Russia can help smooth relations between NATO and the Kremlin, a former senior German diplomat said Wednesday.

Wolfgang Ischinger, a former deputy foreign minister with the Foreign Ministry, said while speaking at an event organized by the Foreign Correspondents' Association in Berlin that the recent move by Turkey and Russia to mend ties could benefit Europe as a whole.

"Normalization of relations between NATO ally Turkey and Russia would certainly be helpful for broader efforts to normalize relations between the West and Russia, between NATO and Russia," he said.

"We can only get to grips with the problems like Iran's nuclear potential or the war in Syria when we have Russia on our side, when Russia joins our efforts."

He added: "The normalization of relations between Turkey and Russia now would be for the benefit for all of us."

Turkey and Russia resumed ties last week following seven months of disruption over the shooting down of a Russian warplane by the Turkish Air Force after violation of Turkish airspace above the Syrian border in November.

NATO-Russia relations soured further following Russia's annexation of Crimea in March 2014 and its support for separatists in eastern Ukraine.

Ischinger said despite difficulties in dealing with a more aggressive Russia, NATO should continue pursuing a twofold strategy toward Moscow, including measures of deterrence and dialogue.

He also warned against further alienating Russia and urged for steps toward building trust.

"In this week's NATO summit we should not give the impression that we are just taking measures of defense and deterrence and neglecting the second pillar," he said. "This second pillar remains to be as important as the first one."

NATO heads of state and government are due to gather in Warsaw on Thursday to discuss increasing the alliance's military presence in eastern Europe, something Russia has always viewed as a threat to its sphere of influence.

They are expected to approve plans to deploy four battalions to Estonia, Latvia, Lithuania and Poland amid concerns over Russia's intervention in Ukraine.

"I believe that it would be very helpful if a high-ranking NATO official, or a representative from a member state, visits Moscow tomorrow or after the end of the summit and informs the Russian government about the conclusions," Ischinger added. "We have nothing to hide."