SIPP declaration question

Hey There, I am thinking of contributing to a UK  SIPP . I am a US citizen but a UK permanent Resident. I am getting conflicting answers to " Do I need to  claim the 20% on my us taxes "?  Do I need to file a 3520 ( A) I believe the SIPP is considered a separate trust ...can anyone shed some  personal light on this? or guide me to a site with a definitive answer? thanks in advance.

I don't know the answer but suggest that instead of posting in this website Help forum, you make get some answers if you asked the question in the US-UK Taxes forum.

https://talk.uk-yankee.com/index.php?board=11.0