Intelligence reports that Iraq could be planning to flood the West with anthrax hidden in duty-free goods was received 13 days before the Government issued an alorts warning.
Home Secretary Mr Jack Straw told the Commons the information reached the Home Office on March 5, but Customs and Excise officers and Special Branch police were not alerted until March 18.
He said this delay was because the intelligence had had to be assessed "in context" as "part of a series of informations" that had become available.
Responding to an emergency question by Liberal Democrat home affairs spokesman Mr Alan Beith, Mr Straw insisted there was no evidence of a specific threat to the UK.
He told MPs the decision to issue the warning had been a "prudent, precautionary measure" after a number of countries received intelligence about possible threats by Iraq to smuggle the deadly anthrax virus.
But he underlined how seriously the authorities were treating the potential menace by disclosing that Britain had summoned a seminar of top EU experts on biological and chemical terrorism which was meeting in the south of England.
Mr Straw also disclosed that the Home Office had released an earlier alorts warning "some time ago", …