Christian development agencies and other organisations have written to the Prime Minister urging the UK to demand an immediate halt to Israel's offensive into Rafah.
Christian Aid, Catholic aid agency CAFOD, Embrace the Middle East, and the Scottish Catholic International Aid Fund (SCIAF) have added their names to the letter that expresses "urgent concern" about attacks this week.
At least 67 people, mainly women and children were killed, but the letter warns that the number will continue to rise and "the beleaguered and strained humanitarian system will fully collapse as need will only rise and access decrease".
The groups say that "red lines are being continuously crossed" and that the UK "appears utterly incapable of restraining Israel in its current attempts".
The say that the UK must use its "full diplomatic pressure" to demand an immediate and permanent ceasefire.
Many people from northern and central Gaza fled to Rafah after evacuation orders were given by Israel ahead of its military offensive that was launched following the October 7 attack by Hamas. Around 1.3 million people are trapped in the city.
"It is one of the very few places where extremely limited humanitarian aid is able to enter the Gaza Strip," the organisations write.
They continue, "We ask you now to use the UK's full diplomatic pressure to demand Israel halt its military campaign, which has already resulted in the killing of 28,000 people.
"Will the UK act now, as red lines are being continuously crossed despite warnings from the UK to Israel on the toll of casualties being 'too high'?
"Or will the UK continue its current path, which each day further is enabling Israel's actions with impunity? Will the UK risk further moral complicity in the ongoing death from Israeli attacks?"
