The US Senate Judiciary Committee on Thursday postponed consideration of four bills to curb gun violence after Republicans said they needed more time to study the proposed ban on military-style assault weapons.

The one-week delay by the Democratic-led committee appears unlikely to change the fate of the bills, all of which appear headed to the full Senate for a vote.

The move comes a day after the panel heard emotional testimony that included pleas for lawmakers to back the proposed assault weapons ban.

Neal Heslin, whose 6-year-old son Jesse Lewis was killed with 19 other children and six adults in the Dec. 14 massacre at Sandy Hook Elementary School in Newtown, Connecticut, said the death toll would have been lower if the gunman had not had the automatic weapon.

But Republicans question whether a ban on assault weapons, which is similar to one that was in effect for a decade before expiring in 2004, would violate Americans' right to bear arms under the US Constitution.

Senator Charles Grassley of Iowa, the panel's top Republican, noted that during Wednesday's hearing the measure's sponsor, Democratic Senator Dianne Feinstein of California, asked for suggestions to improve the assault weapons bill.

Critics of Feinstein's bill, Republicans and some Democrats, say studies indicate the earlier ban had no impact on the nation's homicide rate. But backers say assault weapons have been the firearm of choice in several US mass shootings in recent years.

Besides the bill to ban assault weapons, which faces an uphill fight to pass the full Senate, the other bills call for expanded background checks for prospective gun buyers, a crackdown on the illegal trafficking of firearms, and various improvements to school security.

Support generally has been strongest for the background checks bill, but senators have not reached a detailed, bipartisan agreement even on that proposal.

Committee Chairman Patrick Leahy, a Vermont Democrat, said the panel will take up the four bills next Thursday and it could take a few of debate before voting.