Suella Braverman has been accused of being “out of her depth” after conceding many asylum seekers would need to come to the UK in order to submit a claim.

MPs said there is a “shortage of safe and legal routes” to the UK for asylum seekers after the Home Secretary struggled to explain how an orphaned African child fleeing war and religious persecution, who has a sibling living legally in the UK, would be able to make a claim from abroad.

Political opponents said it shows Ms Braverman “doesn’t understand her own asylum policy”.

Tim Loughton, a Conservative member of the Commons Home Affairs Committee, said “let’s do a bit of roleplay” and told Ms Braverman: “I’m a 16-year-old orphan from an East African country escaping a war zone and religious persecution and I have a sibling legally in the United Kingdom at the moment. What is the safe and legal route for me to come to the United Kingdom?”

In the exchange on Wednesday, Ms Braverman replied: “Well, we have an asylum system and people can put in applications for asylum.”

Mr Loughton then asked: “How would I do that?”

To which Ms Braverman said: “You can do it through the safe and legal routes that we have.”

But Mr Loughton replied: “I’m not Syrian. I’m not Afghan. I’m not Ukrainian… What scheme is open to me?”

“Well, if you are able to get to the UK, you’re able to put in an application for asylum,” Ms Braverman added.

Mr Loughton asked: “I would only enter the UK illegally then, wouldn’t I?

“How could I arrive in the UK if I didn’t have permission to get on to an aircraft to arrive legally in the UK?”

At this point, Ms Braverman asked Home Office officials to step in and respond further.

The department’s permanent secretary Matthew Rycroft added: “Depending on which country you’re from, you could engage with UNHCR (the UN’s refugee agency) and that would be a way of getting leave to enter the UK in order to put in that asylum claim. But I accept that there are some countries where that would not be possible.”

“I think the point is that there’s a shortage of safe and legal routes, other than for specific groups of people, that we have generously offered safe haven to,” Mr Loughton said.

Labour’s shadow home secretary Yvette Cooper said “Suella Braverman doesn’t understand her own asylum policy”, adding there is now no safe, legal route for lone child refugees to rejoin relatives in the UK.

“She’s effectively saying they need to make dangerous journey. Shameful,” she said.

Liberal Democrat home affairs spokesman Alistair Carmichael said: “Never has a Home Secretary been more out of their depth.

“Every day this Conservative Government remains in office brings more embarrassment to our great country.”

Ms Braverman also said the current rate of processing asylum claims was too low and the system was too slow, with caseworkers currently making just one decision a week on average.

She told MPs she wanted this to increase to three per week by May, with an “ambition” to get to four, adding: “There are lots of things we’re looking at. I can’t lie, it’s not easy.”

The Home Office is also paying a retention allowance to stop staff leaving in a bid to help cut asylum backlogs.

If staff stay for a year, they are paid £1,500 more. If they stay for two years or more, they are given £2,500, Mr Rycroft told the committee.

He said: “Retention is an issue, these are amongst the lowest paid in the civil servants.”