Riyadh, Dec. 30 -- : Saudi Arabia on Tuesday, declared the military advances by the UAE-backed separatist forces in Yemen a threat to its national security, and in a sharply worded statement termed Abu Dhabi's recent actions as "highly dangerous," as tensions between the two long-time Gulf allies has spilled out into the open.

Riyadh's strong condemnation came after its foreign ministry decrying the advances of the separatist forces, declared that it was alarmed by what it described as Emirati pressure on separatist forces to carry out military operations near the kingdom's southern border.

The warning followed an announcement by the Saudi-led coalition that it had struck a weapons shipment allegedly sent by the UAE to the separatists.

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