German Chancellor Angela Merkel
German Chancellor Angela MerkelFlash 90

German Chancellor Angela Merkel said Wednesday it was "regrettable" that Israeli Prime Minister Binyamin Netanyahu denied her foreign minister a meeting after the diplomat held talks with radical leftist groups.

Merkel's spokesman said that talks with non-governmental organisations were common during foreign travel and should not set off a rift between allies.

"The chancellor finds it regrettable that a meeting between Foreign Minister (Sigmar) Gabriel and Prime Minister and Foreign Minister Netanyahu did not take place," he told reporters at a regular government briefing.

"It should not be problematic for foreign visitors to meet with critical representatives of civil society."

Netanyahu called off the planned meeting Tuesday with Gabriel after the German diplomat decided to go ahead with talks with Israeli radical groups Breaking The Silence and B'Tselem.

Netanyahu's rare move marked an affront against one of Israel's closest international partners.

Israeli critics of the German funding of radical groups say that it is unacceptable for other nations to undermine a democratic ally by funding radical and subversive organizations which seek to overturn the will of the electorate as expressed in legitimate elections.