Terrorism should be cooperatively fought everywhere, Russian President Vladimir Putin and German Chancellor Gerhard Schroeder said Thursday in a joint declaration in the wake of the school siege tragedy in southern Russia.

The terrorist attack in the town of Beslan in North Ossetia republic that claimed lives of at least 335 people, half of them children, "is a new dimension of the threat international terrorism poses to mankind," reads the document which was adopted by the two heads of state, according to the Kremlin.

Putin and Schroeder had planned to issue the declaration during Putin's scheduled visit to Germany this week, the Interfax news agency quoted Putin's spokesman Alexei Gromov as saying.

However, the two-day trip was put off after a wave of terrorist attacks in Russia.

Gromov said that both leaders decided to publish the document considering "the extreme importance of interaction in combating the terrorist threat," according to Interfax news agency.

"Today, international terrorism, along with the proliferation of weapons of mass destruction, regional conflicts and organized crime,is the most dangerous challenge to the security of our countries," the statement says.

"Russia and Germany condemn all forms and demonstrations of terrorism, whatever their cause may be, as unjustifiable criminal acts."

The statement embodies specific methods for fighting terrorism, Gromov noted.