Busia Senator Okiya Omtatah has said that he will continue fighting until the Finance Act is entirely quashed by the court.
It followed the lifting of an order that suspended the Act by the Court of Appeal on Friday effectively paving way for government to implement the new tax measures contained in the new law.
In a statement on Friday, Omtatah said that the Finance Act contains provisions which are against the Constitution.
"We will not give up until the Finance Act 2023 is entirely quashed by the court because it contains provisions which are parallel to the Constitution," he said.
Omtatah was among the petitioners who moved to court to challenge implementation of the Finance Act, 2023.
The petitioners argued that the tabling of the Finance Bill, 2023, now an Act after President William Ruto assented to it, was done without following due procedure.
They wanted the Finance Act declared unconstitutional, arguing that there is no concurrence of both Speakers of the National Assembly and Senate on matters relating to counties.
In a ruling delivered on Friday, Justice Mohamed Warsame, Kathurima M'Inoti and Hello Omondi said they were persuaded that the applicants satisfied the principles for the grant of the orders sought, and that, public interest tilts in favour of setting aside the conservatory orders by the trial Judge.
The ruling was followed by mixed reactions from leaders and Kenyans.
Finance Committee chairman Kuria Kimani said that services which were halted will now be provided to Kenyans.
Kimani has been at the forefront in pushing for the Finance Act said that he is happy the order had been lifted.
"The Finance Act will now be operational thanks to the Court of Appeal ruling. This means that the manufacturing of fertiliser will now be zero-rated. The excise duty on electric motorcycles is now removed. Rental income tax reduced from 10 to 7.5 per cent," he said.
"Maize, wheat and cassava flour are now zero-rated. Reduction on excise duty money transfer, airtime and internet. Zero rating of parts used for the assembling of mobile phones will make Kenya the lead manufacturer of smartphones in Africa. I am elated."
