President George W. Bush yesterday called new terror warnings in Washington and the New York area "grim reminders" of threats facing the United States, as he again defended his government's decision to increase the threat alert level.

"The elevation of the threat level in New York, New Jersey and Washington, DC is a grim reminder of the dangers we continue to face," Bush said in his weekly radio address.

"Information from arrests in Pakistan, taken together with information gathered by the US intelligence community, indicated that al-Qaeda has cased financial targets in New York, New Jersey and Washington, DC, and has recently updated their targeting information," he said.

"This information was buttressed by other information we already had," added Bush, who is spending the weekend with his family in the northeastern state of Maine.

The Bush administration's decision to raise the terror alert at financial companies and organisations in New York, Washington and New Jersey has been criticized because of its reliance on intelligence preceding the September 11, 2001, attacks.

Bush aides initially acknowledged that most of the information that led to the alerts earlier this week pre-dated the September 11

attacks, then claimed that new data had led to the heightened security measures.

The Republican president is running neck-and-neck in the polls against Democratic Senator John Kerry, who is challenging Bush in the November 2 election.

"My most solemn duty as president is to protect our country, and in the three years since our country was attacked, we have taken important steps to overcome terrorist threats to this nation," said Bush, who on Friday had already defended the decision to raise the terror alert.

In his radio address, Bush noted his decision this week to support the creation of a national intelligence czar, a new position proposed in a report by the commission that investigated September 11.