Hi
You may actually be under split year.
If you qualify for split year then you only report any foreign income for the UK part of the year:
Residence: The SRT: Split year treatment
If you do not qualify then you will need to report all your foreign income to the UK :
Tax on foreign income
The guidance at RDRM12150 at www.gov.uk will help you work out if split year treatment applies.
Based on your comments, no foreign income was earned whilst in the UK so there is nothing to report.