Police yesterday revealed that they had been examining a phone-box which may have been used to deliver one of the two coded bomb warnings, which reduced Saturday's Grand National to chaos.

As the IRA admitted responsibility for delaying the National, the rescheduled race's winner Lord Gyllene was paraded before the media in an all-day victory celebration at his Shropshire stables.

The nine-year-old was tipped as ''the new Red Rum'' by millionaire owner Stan Clarke.

Confirmation that the bomb hoax was the work of the IRA came yesterday in a statement to Irish broadcaster RTE.

The IRA statement said: ''We remind John Major that had he given as much importance to the negotiating of an end to the conflict in Ireland over the past few years as he attaches to the disruption of a single sporting event, a lasting peace settlement would have been closer and conflict and disruption a thing of the past.''

Northern Ireland Secretary Sir Patrick Mayhew, said recent bomb threats and violence had made it more difficult for Sinn Fein to enter talks. ''This latest series of atrocities must affect the time-scale of the process by which people will need to consider any declared ceasefire,'' he said.

''We can't expect people to sit down when across the table there are people who are threatening to supplement their democratic vote with Semtex and bullets and mortars.''

Fingerprint experts and forensic scientists began an examination of the telephone box outside a McDonald's in Moor Lane, Crosby, at 11.45pm on Sunday, said detectives.

q A 14-year-old boy has been charged with placing a hoax bomb after police were called to Liverpool's Croxteth Country Park at 5.50pm on Monday, minutes after the conclusion of the rearranged National. He has been bailed to appear at Liverpool Youth Court in May.