German ex-chancellor Gerhard Schroeder said the EU's planned Nabucco pipeline, which would sidestep Russian territory and supplies, will have to rely on Iranian gas, according to Russian news agencies Friday.

At an energy conference in Kazakhstan's capital Astana, Schroeder said that existing arrangements would only provide enough gas for the Nord Stream and South Stream pipeline projects, both rivals to Nabucco.

Plans for all three projects were justified because Europe needed more and more gas, he said. But the EU must overcome its political differences with Iran in order to secure an agreement over gas deliveries from the Caspian Sea, he added.

Schroeder, who sits on Nord Stream's board and on that of Anglo- Russian oil venture TNK-BP, emphasized that Nabucco presented no threat to the planned Nord and South Stream pipelines. Russian Prime Minister Vladimir Putin, with whom Schroeder is good friends, has voiced similar sentiments in the past.

Putin and Russian President Dmitry Medvedev have also previously said that it is unclear where gas for Nabucco will come from.

Nabucco is intended to make the EU less dependent on Russian gas.

Russian politicians are doing everything they can to secure gas supplies from central Asia and countries formerly in the Soviet Union for Russia's own projects.

Building on the 3,300-kilometer-long Nabucco pipeline is scheduled to start in 2011. From 2014, it is intended to transport 30 billion cubic metres of gas to Europe every year.

An estimated 8 billion euros (11.7 billion dollars) will be spent on the project. Gas suppliers so far under consideration include Turkmenistan, Uzbekistan, Azerbaijan and Iraq.

Copyright 2009 dpa Deutsche Presse-Agentur GmbH