Developing countries, which host most of the world's refugees, could close their borders if Western states persist with aid cuts, the head of the Danish Refugee Council warned on Tuesday.

As countries like Britain and Germany tighten their asylum rules amid anti-immigration sentiment, many are also cutting their contributions to help support millions displaced by violence and climate change around the world.

Charlotte Slente, Secretary General of the Danish Refugee Council, which works in dozens of countries, said she was concerned that poorer states, which take in 75% of them, will also implement new restrictions.

"They are now being a bit abandoned by the donors," she told Reuters in an interview in Geneva. "I'm a little bit afraid for what we're going to see in terms of the reaction among these host nations, when they realise that less money will come in."

She cited an example where Uganda, for years a generous host of refugees from Sudan, South Sudan and Somalia, has started restricting numbers.

Ugandan government officials did not immediately respond to a request for comment.

Other states are also under strain.

Chad has nearly 900,000 refugees from Sudan's civil war, but they are not getting enough aid, and camps are filling up, said Slente, who visited them last month.

The NGO has already had to cut back support to displaced people this year due to funding cuts, mostly by the United States, which previously accounted for 20% of contributions, and has scaled back foreign aid dramatically under President Donald Trump.

The Danish Refugee Council has cut nearly 2,000 posts and scaled back aid in many countries, including nutrition supplies to mothers and their children in places like Cameroon and Afghanistan, Slente said.

Other donors have so far kept contributions to her NGO steady, but Slente expects falling contributions from other European countries as they shift funds to defence.