The couple welcomed their first child, North West, last month.
"Kim and Kanye were talking to the baby when in mid-sentence he asked Kim to marry him. She started to cry and mouthed the word, 'Yes'," femalefirst.co.uk quoted a source as saying.
"This time she wants something different and exotic. She likes how Katy Perry and Russell Brand got married in India with an Indian-themed wedding. She wants that. Kim thinks she's the spitting image of Egyptian goddess Isis, so she has been talking about doing an Egyptian-themed wedding, at the pyramids," the source said.
"She says Kanye digs the idea too. It will cost millions to fly everyone to Egypt, but money is no object," added the source.