I would suggests, as discussed in this article https://www.theguardian.com/commentisfree/2010/aug/15/deficit-crisis-tax-the-rich) a one off 20% tax on the richest 10% of the populatio; which, it is suggested, will raise £800bn. As you will read from the article the idea is very popular with your voters; and as this is a government which says it will listen to the voters, please take heed.