How to handle double taxation on Shares/RSUs

Hi, I was provided with shares as equity by the company I work for - which is a US company. However, the company that officially employs me is based in the UK. I am taxed twice on these shares; - as a portion is withheld to pay local US taxes - as the total amount the shares were bought for with RSUs passed through payroll. For example; 121 shares vested (51 withheld and 70 released) Tax event on payslip at full amount: 121 @ USD 31.73 = USD 3839.33 (GBP 3041.52) Misc one-off deduction in payslip: GBP 1759.56 Firstly - is it correct that as a non-US resident alien working for a UK company I have US shares withheld to pay local US taxes? Second - is there something I should be filing with HMRC to make at least _some_ profit? Thanks in advance for the assist.

Hi billynomates,
As the payment is from your employer, the income should be shown in the employment section if it is included in your P60.
You would then claim credit for the Tax in the foreign section under 'Employment, self-employment and other income which you paid foreign tax on'.
If it's not included in your P60, please include it on the box on the employment page for 'Tips and other payments not included on your P60'. ERSM20193 advises that when RSUs payout at the market value on what is called "dividend equivalents" in either cash or shares, such payments will generally be taxed as earnings in the year they are received.
ERSM20193 - Employment-related securities and options: what are securities: RSUs and dividend equivalents
Thank you.