MHAIRI Black has revealed she was the "last to know" that she was on course to clinch a stunning General Election victory because her father misled her in the hours before the result was announced.

The former student, who became the youngest MP since at least 1832 in May said that her dad - who worked as her election agent - told her the result was "so close" as he provided her with updates from the Paisley and Renfrewshire South count, while she stayed at home playing the guitar and watching TV.

During an interview over lunch with former Newsnight host Jeremy Paxman for the Financial Times, she revealed that her father then suddenly turned to her shortly before the declaration and told her she had been winning all along, saying: "Mhairi, I’ve been lying to you all night. You’ve been winning since they counted the first box. We didn’t tell you because we didn’t want you to work yourself up."

The MP, who overturned a Labour majority of more than 16,000 and eventually beat former foreign secretary Douglas Alexander by more than 6,000 votes said: "It was a bombshell. I was the last one to know."

Ms Black, who is 20 years old, has quickly become one of the SNP's most high profile members at Westminster. Her maiden speech, which won plaudits from across the political divide, has been viewed online more than 10 million times.

In the interview, she branded the Palace of Westminster "stuffy and dusty" and said a suggestion that billions of pounds in public cash should be used to modernise the buildings was "disgraceful".

She said: "Westminster can’t make up its mind whether it’s a museum or a functioning parliament. Of course, it’s an honour to be elected. But it’s just a building. Can you imagine a postman being attached to a particular pillar box?"

Asked by Paxman whether she might spend the next five decades in Westminster, she replied: "I don’t imagine so. I hope we’ll be running our own affairs in Scotland. I’ve no doubt about it. Fundamentally, none of the SNP MPs really wants to be here."