Saudi Arabia has deployed 30,000 soldiers to its

border with Iraq after Iraqi soldiers withdrew from the area, Saudi-owned

Al Arabiya television said on Thursday.

The world's top oil exporter shares an 800km border with Iraq, where Islamic State insurgents and other Sunni

Muslim militant groups seized towns and cities in a lightning advance last

month.

King Abdullah has ordered all necessary measures to

protect the kingdom against potential "terrorist threats", state news

agency SPA reported on Thursday.

The Dubai-based Al Arabiya said on its website that

Saudi troops fanned into the border region after Iraqi government forces

abandoned positions, leaving the Saudi and Syrian frontiers unprotected.

The satellite channel said it had obtained a video

showing some 2,500 Iraqi soldiers in the desert area east of the Iraqi city of

Karbala after pulling back from the border.

An officer in the video aired by Al Arabiya said

that the soldiers had been ordered to quit their posts without justification.

The authenticity of the recording could not immediately be verified.