Priti Patel has yet to appoint a top borders and immigration official amid the Channel crisis, despite the job application closing more than three months ago.
The home secretary is under increasing pressure over small boat crossings after the French government said on Friday that she was “no longer invited” to a crucial summit with European ministers.
French president Emmanuel Macron accused Boris Johnson of failing to act “seriously” in the migrant crisis by making public demands, as he justified the decision to withdraw Ms Patel’s invitation.
It has also emerged that Ms Patel’s department has yet to recruit a director general for Borders and Enforcement – a role aimed at tackling small boat crossings – even though applications closed on 8 August.
The Home Office announced in June it was seeking an “engaging and collaborative leader” for the £149,000 government post as part of a planned overhaul in operations.
The new director general will be expected to oversee 15,000 civil servants, a budget of £1.28bn and a fleet which includes six coastal patrol vessels and five maritime cutters.
A spokesperson for the Home Office said it was “only right” that Ms Patel’s department takes “appropriate time” to find the right person for the crucial role.
But according to the i, which first reported on the still-open position, the failure to recruit for the role and the departure of four senior borders and immigration officials were down to the “toxic” atmosphere at the Home Office.
Citing Boris Johnson’s decision to stand by Ms Patel over bullying allegations, a source told the newspaper: “There is a big turnover of senior staff as people think if there are no consequences for bad behaviour, they can’t carry on working there.”
Labour said the failure to name someone in top borders and immigration role showed that Ms Patel had “completely lost control of this situation”.
Nick Thomas-Symonds, the shadow home secretary, said: “The home secretary is never short on tough rhetoric, but when it comes to effective action she is nowhere to be seen.”
The new director general is set to replace two interim chiefs, Border Force boss Paul Lincoln and Tyson Hepple, in charge of immigration enforcement, as part of a restructure overseen by Ms Patel the permanent secretary.
A Home Office spokesperson told The Independent: “We are in the process of recruiting a new joint Borders and Enforcement director general.
“In the interim we have appointed two excellent acting directors general for Border Force and immigration enforcement who are both dedicated to stopping dangerous small boat crossings and the ruthless people smugglers.”
The added: “It is only right that we take the appropriate time to appoint a candidate of considerable experience and expertise to the new role. They will be announced in due course.”
