SANAA, Aug 18 (Reuters) - Shi'ite rebels in Yemen are receiving financial support from abroad, a government spokesman said on Tuesday, strongly implying Iranian involvement in an armed rebellion that has flared up in recent weeks.

Yemen said earlier on Tuesday that it wanted to arrest 55 rebel leaders and that fierce fighting was under way in northern Saada province, a rebel stronghold -- a day after the government said it was close to ending the uprising.

"There are foreign parties that are giving financial and political support to elements of rebellion and destruction in Saada," the ministry of defence's online newspaper "September 26" quoted Hasan Ahmad al-Lawzi, information minister and government spokesman, as saying.

For proof of this, Lawzi said, one need only look at the coverage of media outlets such as al-Alam, Iran's state-run Arabic-language television station. Lawzi suggested religious sympathies were a factor in the rebels' foreign backing.

The Houthi rebels are adherents of the Zaydi branch of Shi'ite Islam -- a strongly tribal minority in mostly Sunni Muslim Yemen. Iran is predominantly Shi'ite Muslim.

"There are religious authorities that are trying to interfere in the affairs of our country. These authorities are giving financial and political support to acts of terrorism and destruction which are aimed at the heart of the security and stability of Yemen and especially Saada", Lawzi said.

Yemen's foreign minister had met an ambassador to "caution against the continuation of such interference and meddling in Yemen's domestic affairs", Lawzi said, according to the website, without naming the envoy's country.

Yemen has in the past accused unspecified Iranian entities of backing its Shi'ite rebels, but Tehran has denied any Iranian links to the conflict.

The resurgence of a conflict with the Houthi rebels that has erupted intermittently since 2004 compounds the troubles of a country already grappling with secessionist violence in the south and a growing threat from al Qaeda militancy. Yemeni forces have used air strikes, tanks and artillery in an offensive launched a week ago and described by officials as a determined attempt to crush the revolt, led by Abdul-Malik al-Houthi.

The Houthi rebels oppose Yemen's close ties with the United States and say they are defending their villages against government oppression. (Reporting by Mohammed Sudam, writing by Raissa Kasolowsky, editing by Tim Pearce)

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