No it does not come with either a UK or Irish sim card. The watch comes with a European SIM card based in Spain with a Spanish mobile number, in order to provide the great benefit of no roaming charges anywhere within 31 European Countries and the USA. All calls to the SIM card from outside Spain will be charged by your mobile/landline operator at their tariff for calling Spain. As the device is not intended for long communications, the cost of calling the device should not be significant for general use.
Some mobile operators let you add low rate international calls for no additional charge or for a nominal charge, but you must contact them and Opt in. Check with your mobile operator as it varies from operator to operator.