President Park Geun-hye is poised to veto a revised parliamentary law designed to empower the parliament to challenge government enactment Thursday, Cheong Wa Dae said.

The parliamentary law revision bill passed through the National Assembly in late May and was sent for final approval to the Cabinet earlier this month.

Instead of signing the bill into law, Park plans to use her veto power and request the assembly's reconsideration, a presidential official said.

After approval at the Cabinet meeting set for Thursday morning, the request will be sent back to the parliament, the official noted.

Park has denounced the bill as unconstitutional. The National Assembly's tightened grip on government enactment is feared to encroach on administrative and judiciary rights, her office has said.

"As someone who is required to guard the Constitution, the president cannot accept an unconstitutional bill," the official said.

It will be Park's first veto of a bill since she took office in 2013.  (Yonhap)