To elaborate, it's a bit of work to move funds between U.S. brokers. You need a bank in between. A "wire" does that, but it's possible, even likely, that you'll be hit with a wire transfer charge. They're really intended for (expensive) international fund transfers, and Fidelity to IB is not that. Alternatively, you can do this free of charge if you wish:
1. Use Electronic Funds Transfer (EFT) from Fidelity via the
U.S. Automated Clearing House (ACH) domestic system. EFT/ACH is analogous to GIRO in Singapore. Transfer the funds to your U.S. bank or credit union account, assuming you have one. (This is a prerequisite.) You will need the American Bankers Association (ABA) routing number and your account number.
2. Then transfer the funds from your U.S. bank or credit union account to Interactive Brokers, again via EFT/ACH.
Note that IB has a US$100,000 ACH limit per 7 day period.
I don't think IB has an ABA routing number for depositing funds. It's not a bank.