ambiguous or not?

[Nessie]

Hi,
Please have a look at this:

My family is planning a visit to the US, which have issued them visas that are good for six months and expire by the end of the year

This is a mistake correcting exercise and I choose "have" and change it into "has". But do agree this is an ambiguous sentence? I mean: it's hard to understand who/what "issued them visas", right?
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... something we never have again, I know... I guess I really really know..

Sorry seems to be the hardest word...

[Prezbucky]

It should be:

My family is planning a visit to the US, which has issued them visas that are good for six months and expire by the end of the year.

Break it down into separate sentences:

My family is planning a visit to the US. The US has issued them visas. The visas are good for six months. The visas expire by the end of the year.
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Billie Jean is not my lover. Hee.

[Prezbucky]

As for whether or not it's ambiguous, I don't think so: The first "which" must logically refer to "US".
_________________
Billie Jean is not my lover. Hee.