The Home Office has launched an attack on what it calls “activist lawyers” who it says are frustrating efforts to send migrants back to France.

It cited “vexatious” claims that are hindering its attempts to remove migrants from the UK, but refused to say how many remained in the country.

Priti Patel’s office also hit out at “inflexible and rigid” asylum regulations that it says are “not fit for purpose”.

But the comments have been strongly criticised by human rights charities and branded “bully boy tactics”.

The row comes after a record 202 migrants reached the UK by crossing the Channel on Thursday, with more believed to have made the perilous journey today.

The Home Office criticised the Dublin Regulation, which determines which EU member state is responsible for examining an asylum application.

It said it was “not fit for purpose” and said the UK will no longer be bound by EU laws and can negotiate its own returns agreement at the end of this year.

The department also hit out at what it called “activist lawyers” on Friday evening, who it said put in “vexatious” claims to frustrate the process of removing migrants from the UK.

The Home Office refused to say which lawyers it is referring to or how many migrants it is waiting to remove.

But the comments have been strongly rejected by human rights charity Detention Action, which provides support and advice for people held in immigration detention centres.

Bella Sankey, the charity’s director, said: “Is this supposed to be the new compassionate face of the Home Office – inciting dangerous interceptions at sea, flirting with push-backs and scapegoating the French authorities?

“Desperate times see the department falling back on bully boy tactics – when you hear ‘activist lawyers’ think of hard-working professionals committed to upholding the right to life and the rule of law.

“The Dublin returns system is broken, but this is because it shifts the burden for refugee protection to a small number of European countries rather than requiring all European countries to do their bit.”

She added that the Home Office is in for a “rude awakening” when the time comes to negotiate a new returns agreement with France.

The Home Secretary has also sought to level blame at her French counterparts in recent weeks, saying she thought there could be “stronger enforcement measures on the French side”.

Minnie Rahman, public affairs and campaigns manager at the Joint Council for the Welfare of Immigrants, said: “Those being forced to make desperate journeys across the Channel are doing so because they simply have no other options and become reliant on those willing to exploit them.

“The Home Office is deliberately trying to frustrate international law by seeking to return those who have entered the UK, instead of fairly and calmly assessing their claims.

“If the Home Office was truly serious about tackling exploitation and trafficking, rather than trying to shift responsibility on to the French authorities, they should step up and focus on ensuring that there are safe and legal routes of entry to the UK.”