Saudi Crown Prince Mohammed bin Salman arrived in India on Tuesday evening after spending two days in Pakistan. During the high-level summit, the Saudis pledged over $20 billion (€17.6 billion) in aid to Islamabad, and offered to help "de-escalate tension" with India.  

On February 14, a suicide attack killed at least 44 Indian soldiers in India-administered Kashmir. The militant group Jaish-e-Mohammed allegedly ordered that attack. India has blamed Pakistan for the attack, and accuses Islamabad of sheltering militants. Pakistan denies being involved in the attack and has said it would take action if India provided evidence that Pakistanis were responsible.

Read more: India's Narendra Modi warmly welcomes Saudi crown prince

The Afghan government and NATO have made similar complaints, accusing Pakistan of allowing cross-border attacks and providing militants with safe-havens. Islamabad consistently denies these allegations.

Besides persistent security issues, Pakistan's economy is also in disarray. Saudi Arabia is ready to provide assistance, and it marks another chapter in a complicated history that blends together money, militarism and sectarian violence.

For months, Pakistan's new government, led by Prime Minister Imran Khan, has been in talks with the International Monetary Fund (IMF) for a bail-out package.

Read more: India considers action against Pakistan after suicide attack

But Pakistan's economic instability means that any lending would come along with tough structural reforms, including unpopular measures like deregulation, job cuts, slashing subsidies and tax reform.

Khan's new government is keen to avoid these kind of painful decisions. To strengthen its hand in negotiations with the IMF, it has sought help from friendly Gulf countries – and Saudi Arabia was the first to step up.

In recent months, Saudi Arabia, along with the United Arab Emirates, have helped support Pakistan's economy by pledging billions of dollars in loans and investment. It's not the first time Riyadh has come to Islamabad's rescue. The relationship goes back decades.

Saudi-Indian ties

Despite close ties with Islamabad, Riyadh gives New Delhi a great deal of importance. Saudi Arabia is already India's main supplier of crude oil, and ties are being extended beyond energy to build a strategic partnership, India's Foreign Ministry said last week. Bilateral trade is already worth $28 billion (€24.6 billion).

India is hoping for an investment in its National Investment and Infrastructure Fund to build ports and highways. "Trade and investment, defense and security, including counterterrorism, and renewable energy," are all on the agenda for the talks on Wednesday, the ministry said.

Saudi Aramco's investments in Indian refineries, including plans for a project to build a $44-billion (€48.7 billion) facility, are also expected to be discussed.

Old friends in Riyadh

When Pakistan embarked on its secret nuclear weapons program in the early 1970s under the Prime Minister Zulfiqar Ali Bhutto, Saudi Arabia was one of its most trusted supporters.

Riyadh has repeatedly bailed out Pakistan with grants, investments and deferred oil payments. However, the House of Saud and the Pakistani military are the real players sustaining the alliance. In return for financial support, the Pakistani army protects Islamic holy sites and effectively secures the Saudi royal family and its interests.

A major turning point in Saudi-Pakistani alliance was the 1979 Iranian Revolution, which redefined the balance of power in the region. Saudi Arabia saw it as a direct threat. Pakistan, a Sunni-Muslim majority country like Saudi Arabia, shares a 950 kilometer (600-mile) border with Shiite-majority Iran.

Pakistan's military government at the time was threatened by Iran's hopes of "exporting the revolution." It used this common enemy to consolidate its alliance with Saudi Arabia and help extend military rule.

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Pakistan descended into bloody sectarian conflict. It countered Iran-backed Shia groups by arming a host of extremist Sunni groups. Saudi funding poured in to set up vast network of madrassas to promote their version of Islam.

Saudi Arabia and Pakistan, with US assistance, helped Afghan jihadists fight the Soviet Union in the 1980s. And when the Taliban took over Kabul in 1996, Pakistan, Saudi Arabia and the United Arab Emirates were the only countries that recognized their government.

The ties that bind

Considering this history of military cooperation, it came as a shock to Riyadh in 2015 when Pakistan refused to join the Saudi war in Yemen.

A resolution by the Pakistani parliament essentially declared that "Pakistan should maintain neutrality in the Yemen conflict." The Saudis were disappointed with Pakistan's political leadership and they blamed former Prime Minister Nawaz Sharif for letting them down.

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But this setback seems to not have influenced the Saudi royal family's relationship with the Pakistani military. In May 2017, Pakistan's powerful army chief, Gen Raheel Sharif, retired and took up a new job commanding a newly formed, Saudi-led Islamic military alliance.

The appointment, which went ahead without the necessary approvals from Pakistan's civilian government, demonstrated the bond between the Saudi royal family and Pakistan's military leadership.

There is a pattern of Pakistan's top military and intelligence officials taking up highly paid jobs with Arab Gulf nations after they retire. It's a mutually beneficial relationship that has been allowed to continue beyond public scrutiny and away from civilian oversight.

The role of Iran

The Pakistani government insists its relationship with Saudi Arabia is not a threat to Iran. Tehran sees this differently – and its fears may be justified. On Monday, during the Pakistan summit, Saudi Foreign Minister Adel al-Jubeir called Iran the "epicenter of terrorism" in the world.

Read more: Iran's parliament votes to combat financing of terrorism

He went on to list Iran's alleged involvement in proxy wars across the region. The strongly worded remarks were made next to his Pakistani counterpart during a joint news conference in Islamabad.

The occasion made Saudi Arabia's priorities in the region very clear, while revealing Pakistan's limited options in dealing with their Saudi donors.  This is a source of anxiety in Pakistan. And if the Saudi crown prince is offered geostrategic assurance in return for his generosity, these are unlikely to be discussed or questioned in public. It will be a delicate balancing act for Pakistan's civilian and military leaders to reconcile their dependence on Saudi money, while ensuring good neighborly relations with Iran and India.