Immigration reforms seeking to curb English Channel crossings and change how asylum claims are processed have cleared their first parliamentary hurdle.

The Nationality and Borders Bill received a second reading by 366 votes to 265, majority 101, as the number of people making the perilous journey across the Channel to the UK in 2021 approached the entire figure for 2020.

Labour’s bid to block the Bill was rejected by 359 votes to 265, majority 94.

The Opposition’s amendment acknowledged the “need to address the increasing number of dangerous boat crossings” but argued the legislation failed in several other areas.

During day two of debate on the Bill, Conservative MP Damian Collins (Folkestone and Hythe) said fair-weather small-boat crossings by “hundreds of undocumented asylum seekers” have “become a fact of life” for coastal residents.

He noted more than 8,000 migrants have already made the trip this year compared to 8,500 last year.

But opposition MPs warned the Bill will do little to resolve the immigration issues faced by the UK.

Claims of “dog whistle” politics emerged from the SNP benches, while Labour former shadow chancellor John McDonnell claimed some of the language used by those on the Government benches “wouldn’t go amiss at an English Defence League meeting”.

Mr McDonnell’s criticism was labelled “insulting” by some on the Tory benches, who argued the legislation will resolve problems found within the “broken” immigration system.

The Bill includes clauses to allow the UK to be able to send asylum seekers to a “safe third country” and to submit claims at a “designated place” determined by the Secretary of State.

Officials believe the Bill gives the potential to allow for offshore processing centres to be set up overseas, akin to policies used in Australia.

Reports have suggested the UK is considering sharing a processing centre with Denmark in Rwanda and may even revive speculation over suggestions that Ascension Island could be sought as another destination.

Conservative Theresa May, who previously served as prime minister and home secretary, voiced concerns about such a proposal on day one of debate on the Bill – saying she had rejected the option in the past due to “practical concerns”.

The Bill also gives Border Force officers powers to turn migrants away from the UK while at sea, and makes it a criminal offence to knowingly arrive in the UK without permission – with the maximum sentence for those entering the country unlawfully rising from six months’ imprisonment to four years.

It’s become a fact of life that when the weather is good and the sea is calm, hundreds of undocumented asylum seekers will attempt to cross the Channel in small boats

For the first time, how someone enters the UK – legally or “illegally” – will have an impact on how their asylum claim progresses and on their status in the UK if that claim is successful.

Speaking on day two of the debate, Mr Collins urged the Government to “close down these illegal crossing points” and warned of the “growing problem” of illegal entry into the UK by migrants across the Dover Strait.

He said: “For residents on the Kent coast, including in my constituency, it’s become a fact of life that when the weather is good and the sea is calm, hundreds of undocumented asylum seekers will attempt to cross the Channel in small boats.”

Conservative former minister Tim Loughton said the “French government have consistently failed to close off this route”.

He also described the asylum and immigration system as “broken” and “hugely bureaucratic”, adding: “It’s becoming a cash cow for the Home Office, frankly – for example, a leave-to-remain application typically costs £1,033, of which the cost to the Home Office is just £142, that’s a profit to the Home Office.”

The notion that we are overwhelmed with asylum seekers is bogus nonsense, it is not true and yet it is the premise that much of this Bill is written on

But Liberal Democrat former leader Tim Farron said the new Bill is a “charter” for modern slavery and people trafficking.

Mr Farron also said: “The notion that we are overwhelmed with asylum seekers is bogus nonsense, it is not true and yet it is the premise that much of this Bill is written on.

“Now, there is a problem with the asylum system, and that is that there is a colossal backlog.”

SNP MP Chris Stephens (Glasgow South West) added: “I am afraid this Bill exposes the Conservative Party in all its guises, because this Bill is the politics of the dog whistle.”

Conservative MP Alberto Costa (South Leicestershire) welcomed the Bill, saying it could “simplify” British citizenship applications for some.

But Labour’s Richard Burgon (Leeds East) called the Bill “stomach churning”, adding: “This rotten, sick piece of legislation opens the door to offshore detention centres.”

The proposals will undergo further scrutiny at a later date.