Israel's foreign ministry has branded it a "selfie yacht", while Thunberg says she has been "kidnapped" after Israeli forces boarded the vessel.

The British-flagged yacht Madleen, which is operated by the pro-Palestinian Freedom Flotilla Coalition, was aiming to deliver symbolic aid to Gaza.

Israel has intercepted a Gaza-bound aid ship carrying Greta Thunberg and other prominent activists, detaining those onboard, with the vessel being taken to Israel.