Stay up to date with notifications from The Independent Notifications can be managed in browser preferences. All News Sport Culture Lifestyle The Independent reports live from Downing Street as defiant Starmer pledges not to quit UK long-term borrowing costs have surged to a 28-year high, with the yield on 30-year government bonds (gilts) jumping 13 basis points to 5.807%, while 10-year gilts also rose to 5.11%. This increase in borrowing costs, which makes it more expensive for the government to borrow from financial markets, occurred as Prime Minister Sir Keir Starmer 's leadership faced increasing pressure and calls to resign from within his own party. The pound also weakened significantly amidst the political instability, falling 0.6% against the US dollar to 1.352 and 0.2% against the euro to 1.152.…