Recital 21 Rome I REG
Recital 21 In the absence of choice, where the applicable law cannot be determined either on the basis of the fact that the contract can be categorised as one of the specified types or as being the law of the country of habitual residence of the party required to effect the characteristic performance of the contract, the contract should be governed by the law of the country with which it is most closely connected. In order to determine that country, account should be taken, inter alia, of whether the contract in question has a very close relationship with another contract or contracts.