Almost half of British businesses have not made the necessary arrangements to deal with the government's proposed changes to the immigration system once Britain leaves the EU, a new study has shown.

According to a survey from the Resolution Foundation think tank, approximately 30% of UK firms expect citizens from the EU and the European Economic Area to be allowed to move to Britain, as long as they have a job offer.

Some 17% of businesses, meanwhile, expect no changes at all to the current freedom of movement rules, even after Brexit.

However, the think tank warned these expectations were "totally unrealistic", given Prime Minister Theresa May has pledged to slash immigration once Britain leaves the EU.

While the latest data from the Office for National Statistics showed a sharp fall in net migration, 46% of the businesses surveyed said they did not expect any decline in the number of EU and EEA citizens they employ.

"There's a stark gap between what businesses want and expect from our post-Brexit immigration system and what the government has pledged to deliver," said Stephen Clarke, policy analyst at the Resolution Foundation.

"Reconciling these differences, and giving businesses enough to plan for a new regime is absolutely vital."

Brexit negotiations are scheduled to begin next week as Britain kicks off the two-year process that will take it out of the 28-country bloc by March 2019. However, that timeline now looks optimistic after May suffered an unexpected electoral debacle last week, when she saw her party's majority wiped out at an election she did not need to call.

The ruling Conservative Party won 318 seats, 13 less than it had secured two years ago and eight short of an overall majority, meaning it will need support from Northern Ireland's Democratic Unionist Party to govern.

The result of the election is understood to have substantially weakened May's position, both within her own party and in the eyes of Brussels, while simultaneously emboldening Tory MPs who favoured a so-called "soft Brexit" approach.

On Saturday (10 June), Ruth Davidson, the leader of the Scottish Tories, who campaigned for Remain at the EU referendum, urged May to "look again" at her plan to split from the EU after the Conservatives failed to secure a majority.

"I think what's really clear is that the Conservative party, having failed to win a majority, now needs to work with others," she told BBC Scotland.

"And that means we can look again at what it is we hope to achieve as we leave the European Union – and I want to be involved in those discussions."