US Citizen has no income, Need to report to US the income of UK spouse?

OK, so for a long-married couple - one US citizen, one UK citizen with US green card.  Say they lived in the US for many years, but will now move to the UK.  Assume that the US citizen gives up their job and is supported in the UK by the UK citizen spouse, who now abandons their green card.   

Once a full tax year in the UK is completed with no income for the US citizen, could the US citizen file US taxes as "Married, filing separately" and not report the UK citizen spouse's income?  The gist of the question is: is the UK citizen released from paying US taxes once their green card is abandoned, or must they continue to pay because of marriage to US citizen?

The US green card holder must keep filing until the expatriation date on IRS form 8854 and for 10 years after if the the $2million expatriation limit is exceeded.

Wow, thanks very much for a very helpful and specific answer.

So reading IRS Form 8854, it appears that the obligation to continue filing for 10 years would only apply if the UK citizen held a US green card for more than 8 years of the last 15 consecutive tax years.  If the UK citizen was resident in the US for longer than 8 years, but they have only held a green card for less than 8 years, is the correct assumption that the 10 year reporting requirements of section 877 do NOT apply? 

In this case, does anything need to be filed for the UK citizen beyond a 1040+ for the final year up to the date of expatriation?  And back to the original post, does the US citizen only need to declare their limited income, not that of their spouse?

Many many thanks!  I can't believe that this can all get so complicated - it's daunting!  We will be seeking advice on our returns, but we really need to know what the rules are to make some financial planning decisions.

My understanding is as in the form, that if the green card was held for less then 8 years of the prior 15, then no, you do not have to report income.  You also realize the risks involved with losing the green card after 2 years of not being resident in the US.

As you stated, it is probably in your best interests financially to be married filing separately after the first full year that the green card holder is no longer resident in the US, but there are other considerations as well including where you are domiciled, etc etc etc that can make your head spin.

A guya often points out, nothing is a good substitute for sound professional tax advice.

I agree! The rules are complex.  There are planning solutions.  These start with getting the green card formally renounced, but I would think it through carefully before you do this.

Lets say the green card was only about for 5 years.  Then IRC s 877 does not apply, so the two spouses must file separate returns for the part-year unless they elect/have elected to file joint returns under IRC s 6013(g) or IRC s 6013(h).

Filing joint returns can though produce lower tax bills in some circumstances.

I think Kit and I should meet up!

I think Kit and I should meet up!

I'm almost back, November in London I will be waiting around for 22 days to get everything sorted before I can officially work!  I suspect I will be doing a lot of wandering around...