Charities in Scotland have warned they would have to rein in their work or even close their doors if the UK votes to leave the EU, amid warnings that more than £20m of funding is at risk.

The head of a leading charity has warned of the possible effects of a Leave vote, while stopping short of recommending voters pick Remain.

Alistair Dutton, director of Catholic international aid charity Scottish Catholic International Aid Fund (SCIAF) said around 10 per cent of its total income came from the EU but it was unclear what would happen to existing grants in the event of a Leave vote.

He added: "Institutions like universities and charities receive considerable funding from the EU. If the UK votes to leave there’s a real possibility that this funding will no longer be available. This has the potential to have a large impact on our work with poor communities overseas."

Mr Dutton added: “We currently have three EU grants running until 2018 for our work in Nicaragua, Colombia and South Sudan. If the EU contracts were withdrawn immediately we could face a potential loss of £909,000 over the next two years.

“SCIAF will do everything we can to honour the commitments we’ve made to poor communities. However, the loss of funding from the EU would be such a major change of circumstances for us that we would have to re-evaluate our commitments in a number of countries.”

He said that SCIAF and other voluntary organisations were likely to seek government help, if they do find their incomes severely affected. “In the event that the UK does votes to leave the EU, we would urge the UK government to step in to help charities fill the shortfall,” he said.

The comments come after a survey showed that only 18 per cent of charity employees are likely to vote Leave on Thursday.

Many fear not only the loss of direct funding currently received through EU grants, but also further austerity and cuts to the third sector if a financial crash hits the UK economy as a result of a possible Brexit.

Charities in Scotland currently receive £19m a year in European Structural and Investments Funds (ESIF), with past recipients including Enable, Intowork, Action for Children, the Princes Trust and the Scottish Association for Mental Health. However millions more come from other European schemes.

Maggie Lennon, director of the Bridges Programme,which supports refugees, asylum seekers and migrants living in Glasgow, says she isn’t surprised either that the majority of the sector wants to remain in the EU. “We have had EU funding for 10 years and without it we would struggle to survive," she said.

John Downie, director of public affairs at the Scottish Council for Voluntary Organisations (SCVO), which carried out the survey, said it wasn't just funding that influenced charity workers to lean towards the Remain camp. “Given the positive impact the EU has on human rights, employment rights and the rights of people with disabilities, it’s unsurprising that more than 70% of third sector respondents say that they will vote to stay in the EU,” Mr Downie said.