The United States condemned on Thursday the explosions in London that killed some 40 people and expressed condolences to the victims of the explosions.
"This is obviously an attack that demonstrates the barbarity of the terrorists with whom we are dealing," US Secretary of State Condoleezza Rice said in a statement.
"I want to express our sympathy and our prayers for the families of those who have died, and our prayers and wishes for the recovery of the injured," Rice said.
Rice said that the explosions will only strengthen Britain's resolve to fight against terror.
"It will, in fact, only strengthen the resolve of Great Britain, of Prime Minister Blair and his government, and of the people of Great Britain to make certain that terrorists know that they cannot win; that we remain resolved in our determination to root out this scourge against humanity and against civilization," she said.
Britain has been the strongest ally of the United States in the Iraq war.