Welsh ministers decided to work with Amazon in developing a testing portal, which was only ever rolled out in the south east of the country.
Health Minister Vaughan Gething said data issues with the UK-wide system had been resolved so there was no need to continue "developing that Wales-only route".
He said it was not "about being different for the sake of it".
Wales went its own way, while the Scottish and Northern Irish governments Speaking on the BBC's Politics Wales programme, Mr Gething said: "At the starting point we weren't able to take proper advantage of the UK testing programme because we'd only have known if people had a test - the other information wasn't coming back into our health and care system, so the value was really limited.
"Now, we're in a position where those data issues, that really do matter, are going to be resolved.
"That's why I've got some confidence about taking part in the wider UK testing programme.
"So the results will go back on to the patient record, clinicians may be able to see them and make use of them.
"That's really important for us because, whilst we were developing our own track, now we're able to have a consistent approach with other parts UK with information coming back to us. We can use the exact same portal.
"And the question is, now we're able to do that, why would we carry on with developing and implementing a separate portal online here in Wales?"
Asked how much had been spent on setting up the Amazon website, the health minister said he did not have the figures to hand and he was "really not bothered about getting into how much we spent on developing a different portal at a point in time".signed up to the UK government booking portal.
What were the promises were made by Amazon which led to the Welsh Government adopting their system and were they met , and did the Welsh Government ensure in their contract that if they weren't , there would be no financial penalty if it they were forced to scrap it .
How long will it take to implement the new portal , bearing in mind the pressure, that the Welsh Government is under to ease Lockdown in Wales.
Unless we have a vigorous testing system working in Wales . we can't even begin to ease restrictions on peoples movements .
Shurley its time Vaughan Gething considered his position , the argument that changing horses in Mid Stream , seems to wear thin when the horse you are on , looks like it can't carry you all the way to saftey.