Starting when the 114th Congress convenes on Jan. 6, President Barack Obama will face an all-Republican legislature for the first time during his presidency, and Obama made clear on Monday that he will not hesitate to exercise his veto power should attempts be made to roll back Obamacare or weaken environmental regulations.

Since taking office in 2009, Obama has only vetoed legislation twice, according to The Associated Press, the fewest number used by any president in nearly 100 years.

But now, speaking during an NPR interview published on Monday, Obama said he suspects "there are going to be some times where I've got to pull that pen out."

"I'm going to defend gains that we've made in health care; I'm going to defend gains that we've made on environment and clean air and clean water."

The president added that Republicans are "in a position where it's not enough for them simply to grind the wheels of Congress to a halt and blame me."

"They are going to be in a position in which they have to show that they can responsibly govern, given that they have significant majorities in both chambers."

Since the GOP gained control of both houses of Congress in last month's midterm elections, many within the party are anxious to use their newly gained Senate majority to take action against Obama's immigration, health care and climate change efforts.

But to overturn a veto from Obama, Republicans will need to obtain a two-thirds vote in the House and Senate. Since they will only have 54 percent of the seats in the Senate and about 57 percent in the House, the GOP will need to persuade some Democrats to join their cause, reported The International Business Times.

Some issues, like a jobs bill, should pass through without much of a fight, according to incoming Senate Majority Leader Mitch McConnell, R-Ky, who told the AP, "Bipartisan jobs bills will see the light of day and will make it to the President's desk, and he'll have to make decisions about ideology versus creating jobs for the middle class."

"There's a lot we can get done together if the president puts his famous pen to use signing bills rather than vetoing legislation his liberal allies don't like," he added.

Other areas likely to see cooperation include tax reform and global trade deals, while issues most likely to create friction involve Environmental Protection Agency regulations, the Keystone XL pipeline and Obama's unilateral executive action to provide deportation relief to some 5 million illegal immigrants, the AP reported.