It is a very grey area but on the tax credits site it does state right at the bottom of the page that as I just posted anyone who is entitled to tax credits because they are a british citizen can continue to claim them and the husband/wife even with no recourse to public funds in there passport has to be treated as if it where not there I found this by accident looking for something else.
This is as black and white as it gets: ANY spouse is entirely 'there' when it comes to their income, however small. And that includes ANY income you were required to report on your application or renewal form - child maintenance, savings, stocks and shares, etc.
Yes, you are British and can continue to claim, on a new application w/all yours and your spouse's income and assets reported. Even if they are NOT working, you need to report anything they have or get, including alimony and child support payments, social security, etc.
I just had the most unpleasant experience of having gone through a - thankfully successful - appeals process w/regards to our tax credit claim, made just after I received ILR and had given birth to our child.
It was only b/c there was strong written evidence that we had reported ALL our income correctly and in a timely fashion that our appeal was upheld. The errors had been theirs, but the onus of proof was ours.
DO NOT mess around with this! Better for the spouse to tough it out and get working, to go super lean, than to get caught out by this, b/c it's now being run by the IR and they do not play nice.
If you are getting housing benefit, same deal.