Dublin MEP Mr Proinsias De Rossa is taking part in an EU fact-finding mission to Israel and the Palestinian territories.
Eighteen members of the European Parliament are traveling to Israel today and will go on to the Palestinian territories before reporting back to the European Parliament on Wednesday.
The delegation will meet Israeli and Palestinian political leaders for talks. The delegation also plans to visit the Jenin refugee camp that came under heavy Israeli attack and where there are reported to have been many casualties.
Mr De Rossa said the world had been shocked at the way in which the conflict had escalated over recent months with such a tragic loss of both Israeli and Palestinian lives.
He said the use of suicide bombers by Palestinian groups could not be justified but that "it is quite clear that the military operation mounted by Israel has been in breach of international law and in direct contravention of United Nations resolutions".
Mr De Rossa said: "I am also deeply concerned at the damage to civilian infrastructure in the Palestinian areas, much of which was paid for with EU financial aid. I am also concerned that the full story about the number of Palestinian casualties has not yet emerged".