They have been rivals for a long time, but lately things have gone from bad to worse.
We present you 5 keys to understand the conflict between both.
- Religious conflict
The decades-long dispute is aggravated by religious differences.
Each of them follows one of the two main branches in Islam: Iran is largely Shiite Muslim, while Saudi Arabia sees itself as the main Sunni Muslim power.
This religious schism is reflected in the broader map of the Middle East, where other countries have Sunni or Shiite majorities, some of which look towards Iran or Saudi Arabia for support or guidance.
Historically Saudi Arabia, a monarchy and home to the birthplace of Islam, saw itself as the leader of the Muslim world.
However, this was questioned in 1979 by the Islamic Revolution in Iran that created a new type of state in the region, a kind of theocracy, which had an explicit objective of exporting this model beyond its own borders.
- Arab Spring
In the last 15 years in particular, the differences have been exacerbated by a series of events.
The US-led invasion of Iraq in 2003 toppled Saddam Hussein, a Sunni Arab who had been a major Iranian adversary. This eliminated a crucial military counterweight to Iranian influence in Iraq, which has increased since then.
Then, the uprisings in the Arab world caused political instability throughout the region. Iran and Saudi Arabia exploited these disorders to expand their influence, especially in Syria, Bahrain and Yemen, further increasing mutual misgivings.
According to the correspondent of diplomatic affairs of the BBC, Jonathan Marcus, the critics of Iran assure that Tehran intends to establish itself or its representatives throughout the region as regional leaders and achieve control of a land corridor that extends from this country to the Mediterranean.
- Political context
Both countries are engaged in a fierce struggle for regional domination.
According to Marcus, the strategic rivalry in recent times is heating up because Iran, in various ways, is winning the regional struggle.
In Syria, Iranian (and Russian) support for President Bashar al-Assad almost completely defeated the rebel groups supported by Saudi Arabia.
Saudi Arabia desperately tries to contain the increase in Iranian influence and the military recklessness of the young and impulsive Crown Prince Mohammed bin Salman, exacerbating regional tensions.
The prince leads a war against the rebels of his neighbor, Yemen, in part to quell what is perceived as Iranian influence there. But after almost three years, the war is becoming an expensive bet
.
Meanwhile, in Lebanon, many observers believe that the Saudis pressured Prime Minister Saad Hariri to resign in order to destabilize the country where Iran's ally, the Shiite militant group, Hezbollah, is leading a powerful political bloc and controlling a huge armed force.
- The interests of great powers
There are also external interests involved.
Saudi Arabia has gradually received the support of the Donald Trump government, while Israel, which considers Iran a deadly threat, also supports the Saudi effort to contain Tehran.
The Jewish state fears the intrusion of pro-Iranian fighters in Syria, who are increasingly approaching their borders.
Israel and Saudi Arabia, in fact, were the two countries that most resolutely opposed the 2015 international agreement
that limited Iran's nuclear program.
They insisted that he did not go far enough to reduce Tehran's chances of obtaining a bomb.
- Regional geostrategic struggle
But in the conflict between Iran and Saudi Arabia, the geostrategic domain of other countries in the area is also played out. And it is that the map of influences in the Middle East reflects the Shia-Sunni division.
Other Sunni actors are in the Prosaud ranks: United Arab Emirates, Kuwait and Bahrain, Egypt and Jordan.
On the Iranian side is the government of Syria, strongly supported by Tehran, and where groups of Iranian Shiite militias, including Hezbollah, based in Lebanon, have played a leading role in the struggle against predominantly Sunni rebel groups.
The Iraqi government, dominated by the Shiites, is also a close ally of Iran, although, paradoxically, it also maintains a close relationship with Washington, on whom it has depended to obtain help in the fight against the self-styled Islamic State.
- Ideological tensions
The conflict between Saudi Arabia and Iran is, in many ways, a regional equivalent of the Cold War, which pitted the United States against the Soviet Union.
Iran and Saudi Arabia do not fight directly, but are involved in a variety of power wars in the region.
Syria is an obvious example while Saudi Arabia has accused Iran of supplying ballistic missiles fired on Saudi territory by the Shiite rebel Houthi movement in Yemen, an incident that intensified the war of words between the two countries.
But after being stuck in Yemen and being virtually defeated in Syria, Saudi Arabia seems to have its eye on Lebanon as the next battlefield of power.
According to Jonathan Marcus, Beirut runs the risk of falling into a chaos similar to Syria, but few analysts believe that Saudi interests prevail there.
"The conflict in Lebanon could easily attract Israel in opposition to Hezbollah and this could lead to a third war between Israel and Lebanon much more devastating than any of the previous encounters," the BBC correspondent says.
Information source and images:http://www.bbc.com/mundo/noticias-internacional-42036451