Suella Braverman said she “never ignored legal advice” as she faced MPs in the Commons over concerns at an overcrowded migrant processing centre.
The home secretary said she knew “the importance of taking legal advice into account”.
“At every point I’ve worked hard to find accommodation to relieve pressure at Manston.”
She also said illegal migration “is out of control” and spoke of an “invasion on our southern coast”.
Braverman gives statement to Commons – live updates
Labour had accused the home secretary of being silent on the worsening Channel crisis and overcrowding at the Manston processing centre in Kent, where outbreaks of MRSA and diptheria have been reported.
The site is only designed to hold 1,000 people, who are meant to stay for just 24 hours, but there are currently around 4,000 migrants there – more than any UK prison population.
Hundreds more people were moved to the Manston facility yesterday, following a petrol bomb attack at the Border Force migrant centre in Dover.
The home secretary is coming under increasing pressure after a report in The Times claimed she blocked the transfer of asylum seekers from Manston to new hotels and ignored legal advice that the government was illegally detaining people there.
Mrs Braverman is also facing calls to go over security breaches during her time as home secretary under Liz Truss.
New Prime Minister Rishi Sunak has been under pressure over his decision to appoint Mrs Braverman as home secretary since he gave her the job last week, but has stood by her.
The home secretary resigned from the same role in Ms Truss’ government after sending sensitive policy documents from her personal email to former security minister Sir John Hayes and another MP’s aide, breaking the ministerial code.
But she was given her job back just six days later after Mr Sunak took over as prime minister.
In a letter to the home affairs committee released today, Mrs Braverman admitted she sent official documents from her government email to her personal account on six separate occasions during her first six-week stint as home secretary.
She said she apologised to Mr Sunak for the breach she resigned over when the PM reappointed her as home secretary.