(AllHipHop News) Rapper Nicki Minaj has expressed disappointment for having to drop off of Rihanna's highly anticipated Last Girl on Earth Tour. Shortly after an announcement was made about her involvement with Rihannas tour, she broke the news to her fans via Twitter that she would sit the tour out to focus on her upcoming debut solo album. According to Nicki Minaj, the album will hit stores in Fall of 2010 on Young Money/Cash Money/Universal Motown. When I first heard about the possibility of touring with Rihanna, I was thrilled to be included on the ticket," Nicki Minaj stated. I admire Rihanna as an artist and I know it wouldve been a killer line up. Im disappointed that the timing wont work, but I hope well be able to revisit the opportunity in the future."Nicki is currently in the recording studio working on new material for the album. The first single is titled Massive Attack and features Sean Garrett. I dont want to do anything that sounds like what any other female rapper has done, said Nicki Minaj. I want to start a new lane that one day, 10 years from now, girls will say, Im more of a Nicki Minaj type.