Orange has finally released details of its monthly contracts for the iPhone 4 here in the UK, and on their cheapest plans the 16GB iPhone 4 will be available for £169 whilst the 32GB will be a £269 on a 24 month contract.
If you want an eighteen month contract the iPhone 4 will cost you £229 for the 16GB and £319 for the 32GB. They have also released details on the pay as you go iPhone 4 on Orange, this will cost you £480 for the 16GB and £570 for the 32GB.
The pay as you go pricing is about £20 cheaper than a SIM free iPhone 4, so this may be the better option. Their website says that the iPhone 4 will be available from the 24th of June, no detaisl on pre-ordering.