The rapper, 44, reportedly broke down in tears at the party and his new song Welcome to my Life is said to include lyrics that take aim at his troubled personal life.

Lyrics seemingly touch upon his current divorce from the 40-year-old reality star, his Twitter meltdowns and his failed bid for the US Presidency, according to The Sun.

He also likens his marital home in Calabasas, LA, with the Kardashian sister to being like "jail".

On the tune, he raps: "Tell the assassins I escaped from Calabasas."

A source at the Vegas party told the publication: "It’s a very deep, sad song about Kanye, with him reflecting on his marriage with Kim.

"He talks about the kids and mentions her taking everything. After he played this song he paused for like, two minutes, and cried. It was really sombre."

The party was held for the upcoming release of the Gold Digger's 10th album, which is titled Donda after his late mother.

It will be Kanye's first album since splitting from wife Kim in February.

Kim cited "irreconcilable differences" as her reason for filing for a divorce, after the pair got married in 2014.

The duo share four children together - North, 7, Saint, 5, Chicago, 3, and Psalm, 2.

Kanye is currently reportedly dating model Irina Shayk, despite rumours the pair had split.

The model was supposedly left "furious" with claims the pair had broke up.