"There are 11 MPs - more than the NZ First and Green caucuses - who have been sent to Parliament by their communities, and aren't going to be able to scrutinise or hold the Government to account," Bridges said.
"It's a really alarming erosion of the Opposition's democratic rights in our Parliament like we have never seen before. It is an unprecedented situation."
The standing orders committee, which included National, in July agreed there would be merit in cutting the number of select committee places to 96. Bridges said nobody envisioned the current situation, where the biggest party by far was in Opposition.
"We were a Government [in July] ... trying to accommodate the Opposition who wanted that. But now the Opposition doesn't want it. Because back then, it is such a disadvantage to us."
Bridges referred to parliamentary debate in August when Labour MP Trevor Mallard said under his party "select committees will go back to being creatures of the Parliament and not rubber stamps for the executive", with more opposition majorities and chairs.
However, Labour's leader of the House Chris Hipkins said the number of 96 was settled upon because that was the recommendation from the standing orders committee.
"And ultimately Bill English was out there on Friday saying the National Opposition was going to use the select committee process to grind the Government's legislation to a halt. It would be fair to say we are not of a mind to increase the numbers on select committee in order to make it easier for them to do that."
English told media to expect more tension and pressure in Parliament, particularly through the select committee process, saying, "it's not our job to make this place run".
Hipkins said National had been offered a much better deal than Labour received in opposition, including five chairs and five deputy-chairs.
"If they increased the number of seats on each select committee that makes it harder for us to ensure we have a full attendance at each select committee, because it is much more difficult for ministers to find time in their schedules to attend than it is for backbench opposition MPs.
"And ultimately this is just about making sure the Parliament can continue to function and the Government can continue to govern."
Hipkins said if Parliament's business committee could not reach consensus on the select committee issue, the new Government would look to pass a motion in the House. Bridges said that would ensure the new Parliament got off to "a very bad start".
"The Government is using its majority to make the opposition less effective. And that is very worrying."
