Plans to toughen up the UK’s asylum system have been condemned by the United Nations, campaign groups and opposition MPs.

Boris Johnson said the plans set out in the Queen’s Speech would “help crack down on the criminal gangs” behind “illegal entry into the UK”.

The forthcoming “new plan for immigration” legislation amounts to the most significant overhaul of the system in decades and means people who have travelled through a “safe country” such as France or Belgium to reach Britain will not be admitted into the UK system.

For the first time the way people entered the UK – either through legal or irregular means – will have an impact on how their claim progresses.

The UN’s refugee agency has demanded a rethink of the plans.

The UNHCR acknowledged the UK’s right to control its borders, and the need for improvements in the system.

But this “must remain consistent with the right to seek and enjoy asylum”.

The agency warned that expecting refugees to seek asylum in the first safe country would overwhelm gateway countries and see the UK “turn its back” on commitments made at UN General Assembly, and through the Global Compact on Refugees.

“We’re ready to work with the UK on alternative reforms,” a spokesman said.

Enver Solomon, chief executive of the Refugee Council, condemned the “cruel and unfair approach”.

“Providing protection for people uprooted by war and conflict and in need of safety, regardless of how they manage to reach our shores, is a hugely important part of who we are as a nation,” Mr Solomon said.

“We have a long tradition of providing protection for people who have gone on to become proud British citizens, contributing as doctors, nurses and entrepreneurs to our communities.

“Through its new immigration bill, this government is seeking to undermine this vital commitment by unjustly differentiating between refugees based on how they arrived here.”

Liberal Democrat leader Sir Ed Davey said the “cruel asylum plans” would stop people fleeing persecution from seeking sanctuary in the UK.

Green MP Caroline Lucas said: “Targeting desperate people who are putting their lives at risk in the hope of finding sanctuary shows how low this Government is prepared to stoop.”

The Government said the current asylum system was costing taxpayers more than £1 billion a year and in 2019 around 62% of asylum claimants to the UK had entered the country illegally.

The promised legislation is aimed at deterring illegal entry and “breaking the business model of criminal trafficking networks”.

The new laws would make it easier to remove people with no right to be in the UK.

Officials said the plan would increase the “fairness and efficacy” of the system to “better protect and support those in genuine need of asylum”.