In a dramatic event, U.S. President Donald Trump went to social media on Saturday to announce that India and Pakistan (after four days of cross-border conflict) have agreed to a "full and immediate ceasefire."

Behind the scenes, American mediators, as well as diplomatic defenders and regional players, it turns out to be crucial to withdraw nuclear-weapon competitors from the edge.

But, hours after the ceasefire deal, India and Pakistan are trading allegations of fresh violations - underscoring their vulnerability.

India accused Pakistan of “repeated violations” while Pakistan insisted that it remained committed to a ceasefire and its troops showed “responsibility and restraint.”

Before the Trump ceasefire was announced, India and Pakistan were excited about many fears that it would become a mature conflict.

Last month, a deadly radical attack killed 26 tourists in India-managed Kashmir and Pakistan's Arimir Kashmir - triggering an air conflict, artillery days, and by Saturday morning, on Saturday morning, there were accusations of each other's missiles hitting each other's planes.

The rhetoric escalated dramatically, and each country claimed to have caused heavy losses inflicted when thwarting the attacks of the other.

Tanvi Madan, a senior fellow at the Brookings Agency in Washington, D.C., said U.S. Secretary of State Marco Rubio called on Pakistan Army Director Asim Munir to call "may be a key point."

"We still don't understand the role of various international actors, but over the last three days it's clear that at least three countries are working to relegate - the United States of course, but so are the UK and Saudi Arabia," she said.

Pakistan's Foreign Minister Ishaq Dar told Pakistani media that "three strikes" were involved in diplomacy - including Türkiye, Saudi Arabia and the United States.

"One question is whether further escalation can be prevented if the call is after India's initial strike when Pakistan has claimed India's losses and off-road vehicles," Ms Madan said.

This is not the first time that the United States has helped to eliminate the Indian-Pakistan crisis.

In his memoir, former U.S. Secretary of State Mike Pompeo claimed he was awakened to speak with an "Indian colleague" who asked not to be named, who feared Pakistan was preparing nuclear weapons during the 2019 standoff.

The former Indian high commissioner of Pakistan's Ajay Bisaria later wrote that Pompeii exaggerated both the risks of nuclear escalation and the role of the United States in calming conflict.

But diplomats say there is no doubt that the United States has played an important role in undermining the crisis this time.

"The United States is the most outstanding outside player. Last time, Pompei claimed they avoided nuclear war. Although they may be exaggerating, they may have played a major diplomatic role and may amplify Delhi's position in Islamabad," Bisaria told the BBC on Saturday.

However, from the beginning, the United States seemed shocked.

As tensions erupt, U.S. Vice President JD Vance said Thursday that the United States will not be involved in a war that “basically our business is not related”.

"Basically, India has grip with Pakistan... The United States cannot tell Indians to lie down weapons. We cannot tell Pakistani weapons. So we will continue to pursue this through diplomatic channels," he said in a television interview.

Meanwhile, President Trump said earlier this week: "I know very well (the leaders of India and Pakistan) and I want to see them solve the problem...I want to see them stop and hope they can stop now."

Lahore-based defense analyst Ejaz Haider told the BBC that this seems to be the only difference from previous occasions.

Mr Haider told the BBC: "The role of the United States is a continuation of the past pattern, but there is a key difference - this time, they initially stayed motivated, watching the crisis evolve rather than jumping in immediately. They only stepped in to their management to manage it when they saw how it worked."

Pakistani experts say that as the escalation cycle deepens, Pakistan sent a "two-man signal" that retaliated against military revenge while announcing the National Command (NCA) meeting, which clearly reminded the nuclear overhang.

NCA controls and makes operational decisions about Pakistan's nuclear weapons.

This is when US Secretary of State Marco Rubio intervened.

"The United States is essential. Without Rubio's efforts, this would not have happened."

Washington’s connection with Delhi deepened.

Indian Prime Minister Narendra Modi’s personal rapport with Trump, coupled with broader U.S. strategic and economic risks, has pushed the U.S. government’s diplomatic leverage to downgrade the two nuclear weapons competitors.

Indian diplomats saw three key peace tracks that happened this time, just like after Pulvama-Barakot in 2019:

• Pressure in the United States and the United Kingdom
• Saudi Arabia's mediation, Saudi Arabia's junior foreign minister visited the two capitals
• Direct India-Pakistan Channel between two National Security Advisors (NSA)

Despite initially changing global priorities and letting go, the United States eventually stepped in to get involved with the indispensable mediator between South Asian nuclear rivals.

Whether exaggerated by its own officials or covered up by Delhi and Islamabad, experts believe that the role of the United States as a crisis manager is still as important as ever - and complex.

However, suspicion did stay on the durability of the ceasefire after Saturday’s incident, which some Indian media reported was actually contributed by senior military officials in both countries (rather than the United States).

"This ceasefire is destined to be fragile. In the case of high-altitude tensions, it quickly emerges. India seems to interpret the United States and Pakistan in a different way."

“And, because of hastily putting it together, the agreement may lack the proper guarantees and assurances needed in such a tense moment.”