The timing of Lowcost Travel Group’s failure ahead of the peak travel period raised eyebrows in the trade, with claims that Brexit caused the collapse dismissed as “unhelpful” and “untrue”.

The online travel agent and trade supplier collapsed at an unusual time for a holiday firm when it should have collected most revenue from customers.

Steve Campion, managing director of Holiday Discount Centre, estimated Lowcost should have had about £20 million of customer money for holidays yet to be taken.

“If it’s run out of cash now, that’s a pretty big hole in the accounts,” he said. “I find it odd that Lowcost has run out of cash at this time.”

Sources suggested Lowcost was selling rooms for less than it paid for them and yet was one of the UK’s heaviest travel advertisers on Google.

“Given the margins Lowcost was working on, you would have to question that,” said Campion.

The inference that Brexit tipped Lowcost over the edge came from Finbarr O’Connell, a partner at administrator Smith & Williamson.

He said the group experienced “significant market headwinds” before the referendum and “this was compounded by the Leave vote itself” and “fall in value of the pound”.

However, Steve Byrne, managing director of Travel Counsellors, said: “You do not go bust because of two weeks of poor trading. Someone has taken a view at this point in the cash cycle that this was the time to go.

“Anyone who’s saying Brexit is having a dramatic impact on bookings is just not being helpful – and it’s not true.

“In the weeks after the referendum, we saw a reduction, but it’s bounced back. There have been price movements because of the exchange rate, but not massive.”

Lowcost’s concerns about Brexit prompted it to email its customers on June 22 to encourage them to vote Remain.