The Duke of York and the Prime Minister joined relatives of the British victims of recent terrorist attacks at a service in Southwark Cathedral on Wednesday.
The memorial service was to commemorate the 13 British victims of the Sharm el-Sheikh, Kusadasi and Doha bombings.
Mr Blair and his wife Cherie were joined by members of the cabinet including home secretary John Reid and culture secretary Tessa Jowell.
The leader of the opposition David Cameron was also in attendance.
The service was led by the Dean of Southwark, the Very Revd Colin Slee, and the sermon was given by the Bishop of Lincoln, the Rt Revd John Saxbee, reflecting the large number of bereaved families from Lincolnshire.
"Last year bombers turned family holidays into terror and death," said Tessa Jowell. "It is important that we all take time to reflect and remember the victims of these terrorist atrocities."
During the service the names of the 13 victims were read aloud and 13 candles were lit.
Tight security measures were in force around the cathedral with parking bays suspended and Montague Close closed to traffic.