12:35 PM PT -- A rep for Nipsey tells us the shoot was indeed a collab with GQ, but the two are not engaged. However, multiple sources connected to the shoot and to the rapper say the pair definitely did get engaged.

Lauren London said yes to Nipsey Hussle, and then she said yes to climbing on a horse for a super cute engagement photo shoot with GQ!!!

Nispey and Lauren have been keeping their promise under wraps ... but we've obtained pics of their upcoming GQ cover shoot, and sources involved with the production tells us they're definitely engagement photos.

We're told Nipsey and Lauren spent about 2 hours Saturday snapping pics on a residential street in Los Angeles, and the couple seemed super happy the entire time! Must be true love.

Nipsey and Lauren have been dating for several years, and now they're finally ready to take the next big step. No word on when they're tying the knot.

Check out the gallery for more engagement pics, plus Lauren's majestic ride!

Congrats!!!