Fr Peter McVerry has said the eviction ban must be brought back in to avoid a 'further disaster' in homeless figures.
He was speaking as new data shows a record 11,988 people were recorded accessing emergency accommodation in March - an increase of 246 on the previous month.
There were 5,823 single adults and 1,639 families accessing emergency accommodation in the month - including 3,472 children under the age of 18.
Fr McVerry, Founder of the Peter McVerry Trust, told The Hard Shoulder these figures will rise.
"They're a total disaster, in fact, but not surprising," he said.
"What's disastrous is not just the numbers, but the fact that for years now almost every month - with one or two exceptions - the number of homeless people has just being going up relentlessly".
Figure 'will keep on rising'
Fr McVerry said the overall figure does not actually count every homeless person.
"It doesn't include those who are sleeping rough, it doesn't include women and children in domestic refuges, it doesn't include 5,000 refugees who have been granted permission to stay in Ireland but can't move out of direct provision," he said.
"It doesn't include thousands of people who are sofa-surfing: you could double that figure, may be even treble that figure, to get the exact number of people who are unable to provide a home for themselves.
"The figure is a disaster".
Fr McVerry said he expects these figures to increase 'exponentially.'
"I am very, very depressed because this figure is going to keep on rising again and again and again now that the eviction ban has been lifted," he said.
"I expect this figure to go up exponentially - so I think we really are in a crisis".
Fr McVerry said targets set to build more houses will help, but will not be enough.
"The Government is behind target on their housing figures, particularly housing for low-income families, and the pace of delivery is too slow," he said.
"They will make a difference, yes - some people will get housing - but they're not going to make a significant difference to the number of homeless people.
"The eviction ban has got to be reinstated.
"Every single charity working with homeless people has called for this eviction ban to be reinstated, with certain safeguards of course.
"The Government is just refusing to listen to every single charity working with homeless people.
"It's just going to be further and further disastrous[sic]".
Fr McVerry said putting the eviction ban back in place would be 'preferable' to tenants with notices to quit 'overholding'.
"I can't see how some people, who are absolutely desperate and simply have nowhere to go, I don't see how some people will not overhold," he added.
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