Ed Miliband has been criticised for "playing politics" with the ongoing crisis in Gaza after he attacked David Cameron's "inexplicable silence" on the issue.
"The PM has been clear that both sides in the Gaza conflict need to observe a ceasefire," a Downing Street spokesman said.
"We are shocked that Ed Miliband would seek to misrepresent that position and play politics with such a serious issue."
More than 1,650 Palestinians, mostly civilians, have been killed since the start of the conflict, while Israel has lost 63 soldiers and three civilians.
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