Meshaal was referring to increased contacts between Hamas and Western delegations since the Gaza war, including a meeting with a US group that included Jack Matlock, a former American ambassador in Moscow.
'Gaza still wounded'
"Triumphant Gaza today is still wounded. Its houses are still destroyed. It's still under siege and its borders are still closed. Add to this the new steel wall," Meshaal said, referring to a structure being built by Egypt along its border with Gaza to stop the smuggling of arms and goods into the strip.
"Today we do not seek war but if war is imposed on us we will fight fiercely," Meshaal said.
Meshaal said reconciliation with Mahmoud Abbas, the Palestinian president, was needed to strengthen the Palestinian cause but he made no new proposals on how to do so after Egyptian efforts to bring about agreement between the two sides foundered.
Meshaal also said that captured Israeli soldier Gilad Shalit will not be freed unless Israel releases hundreds of Palestinian prisoners.
"Shalit will not to home before the liberation of our prisoners," he told the rally, blaming Israel for the failure to reach a deal on freeing the soldier, who was captured in June 2006.