Philip Hammond, new UK Defence Secretary

Philip Hammond has pledged to ensure that UK defences are robust, as he begins his first full day as Defence Secretary.

Liam Fox resigned from the post on Friday after a week of pressure over his working relationship with friend and self-styled adviser Adam Werritty. In a statement, Hammond said he would "ensure that our defences are robust and that the finances that lie behind them are equally robust".

Shadow Defence Secretary Jim Murphy said there were still many unanswered questions, such as who was funding Werritty's global travels, why were they doing it and why was it allowed to continue for so long. Werritty, a former flatmate of Fox and the bestman at his wedding, handed out business cards suggesting he was his adviser and was present at meetings Fox had with military figures, diplomats and defence contractors.

Questions were raised about who paid for Werritty's business activities and whether he had personally benefited from his frequent access to the Defence Secretary.

Shadow Defence Secretary Jim Murphy said the investigation should be continued.

"What is the flow of money? Liam treated Adam Werritty as a good friend. Adam Werritty seems to have treated Liam Fox like some sort of franchise to make money from," he said.

"So we need to know as part of the inquiry just where's the money? Why has Liam resigned? Let's continue to carry out the investigation and if need be, broaden the investigation further." -BBC