Kim Kardashian West is ''so sad'' to be working on Mother's Day.

The 'Keeping Up with the Kardashians' star, who has 22-month-old daughter North with rapper husband Kanye West, is scheduled to fly to South America to promote her new book, 'Selfish' ahead of the US holiday tomorrow (10.05.15.).

Asked about her plans, the 34-year-old star said: ''I am actually so sad that I am going be in Brazil for Mother's Day, so we're doing something the day before. Mother's Day is kind of pretty low-key.

''I saw my daughter doing a whole arts and crafts thing, her and [my niece] Penelope were. So I'm sure that she made me something really special.''

Kim's daughter has also made something for her mother, Kris Jenner, and older sister Kourtney, 36, for the occasion.

She told 'Extra': ''North prepared this thing for my mom and Kourtney so she'll take over for the day.''

The reality TV star is also gearing up to celebrate her first wedding anniversary with Kanye on May 24, but recently admitted they cancelled their plans to go on safari in Africa.

She added: ''I feel like May is a really busy month for us so I think we just want to hang out and relax. Unless he has something planned, he always has something up his sleeve, he always has something planned, so I don't put it past him to do something really special.''