Almost 30,000 Ukrainians have arrived in the UK, after fleeing the Russian invasion.

Some have travelled on family visas, while others have come via a sponsorship scheme which lets unrelated people host an individual or group.

But concerns have been raised that some men are exploiting the latter scheme to contact vulnerable women.

As of 28 April:

As of 25 April:

Family members and potential hosts have said it takes too long for visas to be approved.

Home Secretary Priti Patel apologised for the "frustrating" delays.

The government had faced pressure - including from some Conservative MPs - to issue emergency visas, or lift visa requirements altogether for Ukrainian refugees, but rejected such calls.

EU countries allow Ukrainian refugees in for up to three years without a visa. More than 5.6 million people have fled to neighbouring countries.

The Ukraine Sponsorship Scheme - also known as Homes for Ukraine - allows those without relatives in the UK to live here.

People in the UK can nominate an individual or a family to stay with them rent-free for at least six months.

Any Ukrainian national - or immediate family member of a Ukrainian national - who was resident in Ukraine prior to 1 January 2022 qualifies.

People with Ukrainian passports can apply online, but those without them have to go to a Visa Application Centre in a neighbouring country.

Those who are granted visas can live and work in the UK for up to three years, and access healthcare, welfare and schools.

They can also bring their pets with them.

Who can apply to host a Ukrainian refugee?

Anyone in the UK - of any nationality, providing they have at least six months' leave to remain - can volunteer to host.

More than 100,000 people signed up on the first day. You must be able to accommodate the refugees in your own home, or another property.

Charities, businesses and community groups can also apply.

Hosts will be offered a tax-free payment of £350 a month for up to 12 months, regardless of how many individuals they support.

The government website says hosts are not expected to cover their guests' living expenses, although they can if they wish.

Local authorities will also receive £10,500 in extra funding per refugee for support services, with additional money available for children of school age.

Do you have to know the refugee you want to host?

In the first phase of the scheme, people can only apply to sponsor a specific Ukrainian individual or family.

Those who don't personally know anyone fleeing Ukraine can still register their interest.

They can also contact refugees through charities, faith groups or local community organisations.

These include:

The government has given Reset an initial grant of £300,000 to run a matching and training service.

Many unofficial Facebook groups have also been set up to connect refugees and potential sponsors.

What are the safety concerns?

The government says everyone who applies to be a host is vetted, and Ukrainian applicants also undergo security checks before being matched.

Local councils are meant to approve each property and complete Disclosure and Barring Service (DBS) checks on all potential hosts. However, basic DBS checks are limited, with "enhanced checks" only requested if there are children involved.

In addition, the BBC has found evidence that some predatory men are trying to use the sponsorship scheme to prey on young women.

In April, the UN's refugee agency, the UNHCR, raised concerns about the UK system, calling for "adequate safeguards and vetting measures to be in place against exploitation".

In EU countries, matching is mainly organised by national authorities and charities, with fewer private arrangements.

The BBC has also learned that some refugees who have arrived in the UK have had to be rehoused after being placed in unsuitable accommodation.

The family visa scheme was initially limited to those hoping to join immediate family in the UK. However, people can now apply if the UK resident is an immediate or extended family member.

It is open to Ukrainian nationals - or immediate family members of a Ukrainian national - who were resident in Ukraine prior to 1 January 2022.

Applications from people without passports must be made at a Visa Application Centre (VAC). Applicants are asked to provide biometric information, such as fingerprints.

Those with a Ukrainian passport can apply online, with biometric information provided after arrival.

People granted family visas can live, work and study in the UK, and access public funds for up to three years.

If you're a Ukrainian national granted permission to stay in the UK on or before 18 March 2022, you can also apply to the Ukraine Extension Scheme.