More than one in three UK mobile phone users worry that they would lose touch with friends and contacts if they lost their mobile phones, research has claimed.

Over half of mobile users do not have a separate address book, and one in five use their mobile as their only record of phone numbers, according to research commissioned by mobile network services company Intervoice.

But the study also claims that over half of mobile users have either lost or had a phone stolen within the past three years, and a quarter have lost two or more phones in the same period.

David Noone, director of sales at Intervoice, said: "We put the numbers in our phones so we can call a friend at the touch of just one or two buttons, and we certainly can't be bothered to write them down in an old fashioned address book.

"The mobile phone plays a key role in modern relationships; take the phone away and the way we manage those relationships falls apart.

"The network is the stable partner in a mobile relationship, not the handset. If the network can act as an address book and mirror those important details, then we might really be able to help the UK 'keep on talking' and resolve the annoyances of lost phones and handset upgrades."

The survey also found that a mere one in 20 people think they can remember all the numbers on their phone, compared to one in four that would struggle to remember five numbers.

Men are more likely to remember their friends', partner's and colleagues' numbers, whereas women are more likely to remember their children's or parents' numbers. Nearly two-thirds of women admitted to not being able to remember their partner's telephone number.