John Allen Chau, originally from Alabama, had travelled to the protected Indian Ocean island - one of the world's most isolated islands - reportedly with the intention of converting the people who live there to Christianity.
However, he was killed by the notoriously independent tribe upon arrival.
Now, the Ambassador-at-Large for Religious Freedom, Sam Brownback, has confirmed the US will not be pursuing an unlikely prosecution of the protected tribe.
According to The Sun, he said: "The US government has not asked or pursued any sort of sanctions that the Indian government would take against the tribal people in this case.
"That's not been something that we have requested or have put forward.
"It's a tragic situation and a tragic case of what's happened, but that's not something that's been asked."
Mr Chau wanted to convert the tribe to Christianity. Credit: Instagram/johnachau
Mr Chau's dad, Dr Patrick Chau, has blamed 'extreme Christianity' for his death, citing the influence of evangelicals as pushing his son to a 'not unexpected end'.
Speaking to The Guardian, he said: "John is gone because the Western ideology overpowered my [Confucian] influence.
"If you have [anything] positive to say about religion, l wish not to see or hear [it]."
In one of Mr Chau's final messages to his parents, he wrote: "You guys might think I'm crazy in all this, but I think it's worth it to declare Jesus to these people.
"Please do not be angry at them or at God if I get killed. Rather, please live your lives in obedience to whatever he has called you to and I'll see you again when you pass through the veil."
The tribe do not welcome visitors. Credit: Survival International
North Sentinel Island is a small island - about the size of New York's Manhattan Island - that lies in the Bay of Bengal. It is part of the Andaman and Nicobar Islands and administratively part of India.
The 26-year-old paid fishermen to help him get across to the island, which is illegal to visit - partly because the indigenous people could be susceptible to diseases.
Campaign group Survival International defended the tribe's right to be left alone, saying: "They [The Sentinelese] vigorously reject all contact with outsiders.
"It is vital that their wish to remain uncontacted is respected - if not, the entire tribe could be wiped out by diseases to which they have no immunity. Contact imposed upon other Andaman tribes has had a devastating impact."
There are thought to be around 150 people on North Sentinel Island and they violently shun all contact with the outside world.
They were filmed firing arrows at a helicopter back in 2004 and killed two fishermen who drifted accidentally into their waters in 2006.
Featured Image Credit: Instagram/John Chau