Kim Kardashian has joked her daughter, North, is already running ''a full marathon.''

The 33-year-old star's 13-month-old baby girl with husband Kanye West only recently took her first steps, but loves being chased around by her parents outside.

The 'Keeping Up with the Kardashians' beauty told E! News: ''If we're outside on the grass, it's like a full marathon. She'll run - she'll do whatever. Inside, she's just a little more cautious. She wants you to hold her hand, or she has this little shopping cart that she likes to walk around.''

The reality TV star announced her daughter had started walking last month on her Instagram page, posting an adorable picture of her kissing the little girl, who was wrapped in a yellow towel, with the caption: ''Our baby girl finished one week of swimming lessons today then took her 1st steps right when she got out of the pool!!!! Mommy & Daddy are so proud of you!!!! Photo cred: Daddy (sic)''

Kim and Kanye, 37, who have been living with her mother, Kris Jenner, since North was born in June 2013, recently purchased a new $20 million mansion in Hidden Hills, Los Angeles and they are excited to move in.

She said: ''[We're] moving out of mom's house ASAP!''

The couple, who got married in June, are set to sell their $11 mansion in Beverly Hills, as they got fed up of waiting for their extensive renovations to be completed.