The transaction increases the company’s stake in the project to 45%.
A planning application has been made for the proposed B-2Z side-track appraisal well at the project, the company also noted in a stock market statement.
The application is for the drilling operation, associated testing and, in the event of project success, long term production of hydrocarbons.
It is slated that the programme will kick off in the second half of 2021, subject to planning approval.
“Union Jack's technical team believe that Biscathorpe represents a material and commercially viable hydrocarbon resource that remains un-tested,” said David Bramhill, executive chairman.
"The collective extensive technical information analysed over the past months, combined with APT's conclusions on the likely presence of good quality oil, have materially upgraded the resource potential and economic value of the Biscathorpe project in our view, further supporting our opinion that PEDL253 remains one of the UK's largest onshore un-appraised conventional hydrocarbon licences.”
The chairman added: "Any potential Biscathorpe oil development will be important to the UK as any indigenous production delivers a lower carbon footprint when compared to imported alternatives and it will also provide additional economic benefits to both regional and local communities."