Liberal Democrat MP Jenny Willott is to quit her government post to enable her to vote against raising tuition fees.
Ms. Willott MP is parliamentary private secretary to Lib Dem colleague Energy Secretary Chris Huhne.
The Cardiff Central ward includes campuses and student accommodation for Cardiff University, UWIC, Glamorgan University and the Royal Welsh College of Music and Drama.
MPs are voting on whether to raise the cap on tuition fees for students from England to a maximum of £9,000 a year.
In Wales, basic tuition fees will rise to £6,000 per annum, or £9,000 in some circumstances.
But the assembly government will meet the cost of extra fees for students from Wales attending any UK university.
“Having considered the motion and discussed the issue with my constituents, my local party and my parliamentary colleagues, I will be voting against tonight’s tuition fee motion.
In a statement on her website Ms Willott confirmed her resignation and intention to vote against a rise in tuitions fees:
“I believe that many aspects of the proposals are better than the current system, including abolishing up-front fees for part-time students and generous support for young people from less privileged backgrounds. However, overall I cannot support the package.
“I will therefore resign my role as PPS to the Secretary of State for Energy and Climate Change. I remain fully supportive of the coalition, Nick Clegg and Chris Huhne. Together, we are delivering progressive, Liberal Democrat policies in Government and I am proud of what we have achieved so far.
“My decision to resign as PPS and vote against the Government was extremely difficult. However, I fully respect the individual decisions that each of my colleagues has made.
“I remain fully committed to supporting the coalition Government and I’ll continue to fight for the people of Cardiff Central and Wales, albeit from the back benches.”