Kim Kardashian has served Kris Humphries' ex-girlfriend with a subpoena.

The socialite's lawyers are keen to speak with Myla Sinanaj - who began dating the basketball player in January - to find out whether Kris said anything to her in relation to his claim that the 72-day marriage was fraud. Kim's lawyer is also said to want details of hundreds of text messages and emails between Myla and Kris.

According to gossip website TMZ, Kris initially hid the relationship because he was worried it would impact on the divorce case as he and his representatives felt him moving on just over two months after he and Kim split would make it appear he wasn't "devastated" by the reality TV star's decision to file for divorce despite his previous statements.

Myla's lawyer previously admitted his client would be prepared to help Kim in her divorce proceedings.