Leaving My Job... For Another

HELP!!!
I am currently working under contract in Taipei. The company I work for sponsors my Visa and ARC, however in the contract it stipulates that I have to pay should I terminate my employment regardless of any notice.
Moreover, I have just been offered a position beginning August 1st. My question then is what are the ramifications for leaving my current job?
Anyone with experience leaving one job for another (legally) PLEASE help me. I am on a time limit and really stressing :loco:
Cheers!