The 25-year-old's current deal expires at the end of the season and many of Europe's top clubs, namely Clermont and Toulon, are said to be monitoring his services.
"I've told Cardiff and the WRU that I want to extend [my contract] and sign here," Warburton told BBC Radio 5Live.
"I'm awaiting an offer. I haven't received anything yet, but that's my preferred option at this moment in time."
Warburton led the Lions to a 2-1 Series win over Australia this summer.