Ian Paisley, himself a Christian, also called for the Equality Commission in Northern Ireland's funding to be reviewed after its case was rejected by the Supreme Court on Wednesday.
Five justices dismissed the claim that Ashers Bakery (general manager Daniel McArthur pictured above) had discriminated against a gay activist by refusing his order for a cake to be decorated with a pro-gay marriage slogan.
Mr Paisley wrote on Twitter: "I have written to the Secretary of State for Northern Ireland calling for a review of funding for the equality commission.
"After such a decisive finding by the Supreme Court, the equality commission's immediate response has been to threaten to waste more public money on this case. Stop it now!"
The Equality Commission has yet to reveal whether it will challenge yesterday's judgement.
I have written to the Secretary of State for NI calling for a review of funding for the equality commission. After such a decisive finding by the Supreme Court the equality commissions immediate response has been to threaten to waste more public money on this case. Stop it now!
— Ian Paisley MP (@ianpaisleymp) October 10, 2018
The Christian Institute, which has supported Ashers, revealed more than £250,000 had been spent defending the bakery in the case - meaning the cost of the case has balooned to more than half a million pounds to date.
Mr Paisley, who is the Democratic Unionist Party MP for North Antrim was suspended from the House of Commons for 30 days last month for failing to properly declare an international trip he took at the expense of a foreign government.
The Commission declined to comment specifically on his latest comments.
Please read our statement in relation to the judgment given this morning by the Supreme Court in the case of Lee V Ashers Baking Company Limited and Others https://t.co/UT9pnXSSNW pic.twitter.com/BBHGRARSnp
— Equality Commission (@EqualityCommNI) October 10, 2018
Chief commissioner, Dr Michael Wardlow said: "The Supreme Court has overturned [the findings of junior courts] and we will have to look at the implications of its judgment carefully.
"There is a concern that this judgment may raise uncertainty about the application of equality law in the commercial sphere, both about what businesses can do and what customers may expect; and that the beliefs of business owners may take precedence over a customer's equality rights, which in our view is contrary to what the legislature intended."
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