The politician, who has been either MP or AM in Wrexham for 20 years, said he could also put up independent candidates in Denbighshire and on Anglesey.
Dr Marek, who has been either MP or AM for Wrexham for 20 years, was replaced as the candidate by his former secretary after a series of disputes with Labour colleagues in Cardiff Bay and in his constituency.
The business secretary was summoned to the Commons on 20 February to explain his decision, after Conservative MP James Clappison tabled a question on the issue.