Officials in Washington appealed Sunday for balance between securing the US Capitol and public accessibility after the second deadly attack this year targeted the seat of American democracy.

A policeman was killed and another wounded Friday after a man rammed through security and crashed into a barrier at the complex, forcing it into lockdown less than three months after a mob insurrection at Congress.

Capitol Police shot the driver dead as he jumped out the car and lunged with a knife.

The incident has sparked debate over whether fencing around the 59-acre (24-hectare) campus, much of which was dismantled two months after the January 6 attack, should have been kept in place.

Missouri Senator Roy Blunt, the head of the Republicans' Senate policy team, warned against ring-fencing the complex of around 20 buildings from the public.

"I think it would be a mistake for fencing to be a permanent part of the Capitol," he told ABC's "This Week," noting that barriers had been "right there when the car drove through."

Retired Lieutenant General Russel Honore, who led a security review after the January 6 attack, said lawmakers on both sides of the aisle had affirmed that safety was their top priority -- while making sure the building is "100 percent" accessible. 

"This is something that is valued by every member of Congress we spoke to in the six weeks we were there, and that they want public access," he told ABC.

"That comes... with a balance, with reengineering, with resources needed to the Capitol Police, with upgrading our cameras and sensors and the barriers around the Capitol."

Blunt has co-sponsored a bill alongside Democratic Senator Chris Van Hollen to prevent funding for permanent fencing around the Capitol.

"The Architect of the Capitol, along with the Capitol Police Board, we've given them recommendations," Honore added. 

"The Corps of Engineers is standing by to reinforce the outer grounds of the Capitol with contractors coming in to put advanced fencing that can come out of the ground as required, that can provide more sensors as well as an integration of the cameras."

He also called for funding for more police officers at the Capitol and suggested more than 200 National Guard troops could be deployed as long as two years, as they were after the September 11, 2001 attacks.

"We've given them the plan," he said. "We worked the plan hard. Now it's time for Congress to work the plan."