The Saudi foreign ministry issued the declaration on Saturday, citing what it described as continued Iranian attacks on Saudi territory.
Saudi Arabia has come under attack by hundreds of Iranian missiles and drones since the start of US-Israeli war on Iran, the vast majority of which have been intercepted, authorities said.
The ministry said in a statement that continued Iranian attacks would lead to further escalation and have "significant consequences" for current and future relations.
Iran was targeting Saudi Arabia's "sovereignty, civilian sites, civilians, economic interests, and diplomatic missions within the Kingdom", the statement said, calling it a violation of UN resolutions, international law and "the principles of good neighbourliness".
On Wednesday, the Saudi foreign minister said the kingdom reserved the right to act militarily against Iran and any trust with Tehran had been shattered following recent attacks.
Saudi Arabia and Iran re-established diplomatic ties in 2023 as part of an effort to calm tensions after years of enmity that saw them back opposing political and military factions in the region.
The US-Israeli war on Iran and Tehran's subsequent attacks on Gulf neighbours have disrupted oil and natural gas exports from the Middle East and forced production stoppages.
with dpa
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