Rajapaksa, who visited Palestine in January this year, has been a long-time supporter of the Palestinian cause and is the Founder President of the Sri Lanka Committee for Solidarity with Palestine.
"It is my hope that the violence in Gaza is halted and peace prevails in the region," Rajapaksa had said last month on his Twitter account.
Sri Lanka recognised Palestine as a state in 1988.
During his visit in January, the Government of Palestine conferred Rajapaksa with the "Star of Palestine" - the highest award of the State of Palestine - for the President's continued support and commitment to the Palestinian cause.
The recent spate of violence in the Gaza strip has killed 1,939 Palestinians and 67 Israelis since Operation Protective Edge began on July 8.