In-kind transfer of TFSA securities to an RRSP - US tax implications

[taxenthusiasm]

I am wondering what the US tax implications would be for transferring securities in-kind from a TFSA to an RRSP as a tax resident of both the US and Canada. Would this be considered a deemed disposition and require capital gains to be reported on a US return? For example, this would be relevant when repaying a Home Buyers' Plan RRSP withdrawal using TFSA securities; if possible, it would be ideal to avoid officially liquidating the assets in question and realizing a taxable capital gain. Any citations to IRS guidance or professional commentary on this specific scenario would be appreciated.