President Obama has said there will be "shame" on himself and the American people if pledges to bring in tougher gun safety laws after the Newtown school massacre go unfulfilled.
More than 3,000 gun deaths have occurred in the US since Adam Lanza shot dead 26 children and staff at Sandy Hook Elementary School in Connecticut in December.
More shocking details of the speed of the attack and the arsenal of weapons Lanza owned have been released today.
But, as ITV News Correspondent Geraint Vincent reports from Washington, DC, Mr Obama still faces great difficulty in translating anger at the massacre into legislation aimed at curbing the public's right to bear the most powerful of arms.
More top news
The man who carried out the Westminster attack is thought to be British born and was once investigated by MI5, the Prime Minister has said.
Jason Day, who lost his father to stomach cancer at the age of 12, broke down in tears as he explained his shock exit during the WGC event.
The Gunners are set to offer £25 million to land their desired summer target while Chelsea will rival Manchester United for a raid on PSG.