Thomas Cook, which on Friday secured new funding from its banks to enable prevent it defaulting on its loans, said bookings in Britain have dropped by 30 percent this week with customers spooked by uncertainty over the company's future.

The world's oldest travel firm, which struck an agreement with its lending banks late on Friday enabling it to borrow an additional 100 million pounds, is under pressure to restore confidence among customers.

We were down 30 percent on bookings which is of course substantial but, on the other hand, it could have been much more had our customers not shown loyalty to us, Acting Chief Executive Sam Weihagen told the BBC in an interview on Saturday.

Shares in Thomas Cook crashed on Tuesday after Europe's second-biggest travel firm by sales asked lenders to come to its rescue for the second time in five weeks.

In an attempt to restore consumer confidence, Weihagen, who took up the position of interim CEO following the resignation of industry veteran Manny Fontenla-Novoa in August, published an open letter expressing his confidence in the company's future.

Thomas Cook today is an even stronger and more confident company. You can be sure that your holiday really is in safe hands with us and so, we look forward to welcoming you to one of our stores, our websites, onboard our aircraft and into one of our many thousands of resorts worldwide very soon, he said.

TUI Travel, which owns the Thomson and First Choice chains, has looked to cash in on its rival's misfortune, placing advertisements in national newspapers stating: Another holiday company may be experiencing turbulence, but we're in really great shape.

(Reporting by Matt Scuffham; editing by Keiron Henderson)