Two Ukrainian advocacy groups in the United Kingdom announced that they intend to file a lawsuit Monday against the UK’s Home Secretary, Priti Patel, over processing delays for thousands of Ukrainian refugees entering the UK.

The Russian invasion of Ukraine has left more than 5.5 million Ukrainians in search of refuge, according to the UN Refugee Agency. The UK moved to allow Ukrainians who have relatives in the UK to join them by starting a program known as the Ukraine Family Scheme in March 2022. However, less than half of the 86,100 Ukrainians who have applied for visas under the scheme have arrived in the UK.

As Home Secretary, Patel has been accused of causing delays that have led to thousands of Ukrainians being stuck in their home country at risk of injury and death. The Home Office, which is in charge of approving visas, has failed to complete many applications, causing a “chaotic” backlog. The groups Vigil 4 Visas and Taking Action Over the Homes for Ukraine Visa Delays are preparing to launch legal proceedings through their immigration attorney, Amanda Jones, on behalf hundreds of Ukrainians.

The Shadow Home Secretary, Yvette Cooper has called the delays “inexplicable and disgraceful,” calling for transparency in the visa process for affected Ukrainians. Charities such as the Here for Good Project have also voiced concern over the handling of the Ukraine Family Scheme, stating that some families are considering returning to the dangerous environments due to the “precarious situations in Europe.”