Germany's leader has told Russian President Vladimir Putin that the Kremlin needs to encourage civil society as well as push for technological modernization.

Putin and German Chancellor Angela Merkel are touring a major trade fair in Hannover on Monday. The trip underlines Russia's interest in developing foreign trade, including further business ties with Germany.

At the opening of the fair on Sunday, which both leaders attended, Merkel said real modernization is enhanced by a strong civil society. Germany's ties with Russia have become increasingly strained over the Kremlin's heavy-handed response to opposition groups and pressure on non-governmental organizations.

Merkel argued at the fair's opening that Moscow should give "non-governmental organizations — the many groups that we in Germany know as motors of innovation — a good chance in Russia."