Britain said on Monday it plans to ban all wings of Hezbollah due to its destabilizing influence in the Middle East, classing the movement as a terrorist organization.
London had already proscribed Hezbollah's external security unit and its military wing in 2001 and 2008 respectively, but now wants to outlaw its political arm too.
"The Home Secretary must therefore now demonstrate that this decision was taken in an objective and impartial way, and driven by clear and new evidence, not by his leadership ambitions," a Labour spokesman said.
Asked about the comments, Prime Minister Theresa May's spokesman said it was for Labour to explain their decision.
"Hezbollah itself has publicly denied a distinction between its military and political wings. The group in its entirety is assessed to be concerned in terrorism," he added.
"The links between the senior leaders of Hezbollah's political and military wings as well as the group's destabilizing role in the region mean that the distinction between the two wings is now untenable," he concluded.
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