Kanye West proposed to Kim Kardashian while one of his own songs was playing.

The rapper reportedly popped the question to his reality star girlfriend - with whom he has four-month-old daughter North - with the help of a 50-piece orchestra who played Lana Del Rey's 'Young and Beautiful', before the band serenaded Kim with Kanye's chart-topping hit 'Knock You Down', which also features Keri Hilson and Ne-Yo on record.

According to E! News, the hip-hop star rented out the whole of San Francisco's AT&T Park for the special occasion, which also marked Kim's 33rd birthday yesterday (21.10.13).

As he got down on one knee and presented her with a 15-carat diamond ring by celebrity jeweller Lorraine Schwartz, fireworks and Roman candles exploded in the sky.

Kanye's romantic gesture was completed by a sign above the playing field, home to the San Francisco Giants, which flashed with the message, ''PLEEEASE MARRY MEEE!!! (sic)''.

While baby North was absent from the occasion, all of Kim's close family and friends were secretly waiting in the stands and swarmed out onto the pitch to congratulate her when she accepted his proposal.

Kim's sister Khloe appeared to confirm the news, expressing her delight at the engagement on Twitter.

She gushed: ''Wow!!!!! Am I dreaming??!?! / Tears of JOY!!!!!!! Wow!!!!!! (sic)''