He met U.S. President, George W. Bush, in Washington and British Prime Minister, Tony Blair, in London.
He met George W. Bush and Tony Blair at the same time.
The text says GWB was in Washington and Blair was in London. 
( z1 meet :ARG0 ( z2 he ) :ARG1 ( z3 and :op ( z4 person :name ( z5 name :op "George" :op "W." :op "Bush" ) ) :op ( z6 person :name ( z7 name :op "Tony" :op "Blair" ) ) ) :time ( z8 time :ARG1-of ( z9 same ) ) )