The jobs I have seen have all required a teaching certification (a UK one -- a US certification is largely irrelevant here, unless you're teaching in an American school or, in some cases, a private school). Granted, though, the jobs I would be looking at are for secondary schools (ages 11 to 16) and colleges (ages 16-18). If you're wanting to teach at a university, you might have a better chance of getting a job without a teaching certification. It might be worth looking at some vacancies to see what requirements they have listed. I've just looked at a few for my local universities and for lecturing positions, there's a heavy emphasis on past research and all of the listed faculty have their doctorates (with the exception of three research associates with their MScs). One of the desired characteristics on the person spec is some formal training in tertiary level education.
You can always gain your teaching qualifications here, though you'll be paying international fees for the first three years. I do know that it is possible to gain UK certification by what really amounts to another student teaching experience. You'll have to be "sponsored" by an LEA and will undergo two years of supervised teaching and portfolio building, etc.
