Saudi Arabia has been on a tear this week: launching a massive purge inside the royal family, blockading Yemen where millions risk starvation, and allegedly forcing the resignation of Lebanon’s prime minister. Now it stands accused of “declaring war” on the same country.

The last tidbit comes from the leader of Iran-backed Lebanese militia Hezbollah, Hassan Nasrallah, who said Friday that Saudi Arabia’s actions amounted to a declaration of war against his country.

Nasrallah’s comments come on the heels of the shock resignation of his country’s prime minister Saad al-Hariri Saturday, which his party believes was orchestrated by Saudi Arabia in a bid to increase tensions with archrival Iran.

Senior Lebanese officials have accused Saudi Arabia of kidnapping Hariri and controlling the former leader’s every movement.

Riyadh denies these claims, saying he is a free man. Hariri, for his part, blamed his resignation on Iran’s meddling in Lebanese politics. But the Kingdom has continued to act aggressively toward its impoverished neighbor, accusing the Lebanese government of declaring war on it and taking the extreme step, along with Gulf allies, of urging its citizens to leave the country immediately.

“I’d be lying if I told you I wasn’t extremely worried.”

Taken together, this week’s developments have dramatically raised the chances of conflict in Lebanon, analysts said.

“Things are not developing in the right way and it would take a small miscalculation to have a big conflagration,” Michael Stephens, a Middle East expert at the Royal United Services Institute told VICE News.

“I’m not saying war is imminent but we’re at a very, very tense moment, as tense as I can remember it.”

Here’s what you need to know.

Lebanon is a battleground between Saudi Arabia and Iran

Lebanese politics has been in turmoil since Hariri abruptly announced his resignation in a televised address from Riyadh. Hariri, the scion of a Sunni political dynasty who has been under the political patronage of Saudi Arabia, blamed the kingdom’s enemy Iran and its Lebanese proxy Hezbollah for his resignation, accusing them of hijacking the country’s politics.

Lebanon is a fragile multi-confessional democracy whose politics relies on delicate compromise between its various faith communities: Sunni, Shiite and Christian and Druze.

“He’s definitely not free to come and go as he pleases.”

Lebanese politics has long been a theater for regional archrivals Saudi Arabia and Iran to compete in their geopolitical battle for influence across the Middle East. With neither power keen for a direct confrontation, which would prove costly and potentially catastrophic, they have instead jockeyed for influence in smaller, weaker countries in the region.

In Lebanon, Saudi Arabia has long backed Sunni politicians like Hariri with massive financial support, while Iran has channelled support to its Shiite proxy Hezbollah — a militia with its own political arm, considered far more powerful than the Lebanese state.

Experts agree that Saudi Arabia is behind Hariri’s departure

Middle East analysts say it’s clear that Saudi Arabia was behind Hariri’s departure, with Chatham House’s Lina Khatib calling the kingdom “the main instigator of his decision.”

Hariri, the son of a long-serving prime minister who was assassinated in 2005, came to office just 11 months ago in a coalition government that included most Lebanese parties, including Hezbollah.

Stephens said Saudi Arabia, which had backed Hariri as their man to push back against Iran’s growing influence in Lebanon, had lost patience with his failure to do so, and pressured him to stand aside.

“They’ve invested heavily in him and I think they feel they’ve not got bang for their buck,” he said. “He’s someone that they will keep away from the Lebanese political scene while they look for an alternative to push back against what they see as deep Iranian interference in the country.”

France and Germany, the first Western powers to comment on Hariri’s status, said Friday they believed that the politician was not being held against his will, but Stephens disagreed. “He’s definitely not free to come and go as he pleases.”

Lebanon’s crisis couldn’t come at a worse time

Tensions are running white hot in the region right now. Iranian-backed Houthi rebels in Yemen fired a missile at Saudi Arabia Saturday, as the kingdom’s Crown Prince was carrying out a major purge of the royal family and business elite. “We see this as an act of war,” Saudi foreign minister Adel Jubair told CNN. “Iran cannot lob missiles at Saudi cities and towns and expect us not to take steps.”

The Saudi maneuvers also come as the U.S. has taken a harsher stance on Iran, one that would align with Israeli and Saudi interests, said Khatib. She said this will likely lead to efforts to bring increased political and economic pressure on Iran, including attempts at driving a wedge between Russia and Iran in Syria.

Khatib said the calls from Saudi Arabia, Bahrain, the United Arab Emirates and Kuwait for their citizens to leave Lebanon was about sending a political message and increasing pressure on Hezbollah inside Lebanon. “The orders are … a sign that pro-Saudi Gulf countries are disengaging from the prospect of any compromise with Iran,” she said.

Stephens said the situation had significantly raised the prospect of war in Lebanon.