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Green Party leader Zack Polanski has defended his decision to miss a debate at his party's conference on a controversial motion declaring Zionism a form of racism.

Questioned by presenter Nick Robinson on BBC Radio 4's Today programme, he denied deliberately avoiding the debate, saying he had been campaigning in the Holborn and St Pancras by-election.

The motion, which was passed by party members, defined Zionism as an ideology supporting an "ethnonationalist Jewish state" and backed a single democratic Palestinian state encompassing present-day Israel.

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