Reeves to announce major change to fiscal rules releasing £50bn for spending

After weeks of speculation, chancellor will tell IMF in Washington that UK's debt measure will be redefined to permit borrowing for investment

Rachel Reeves will announce at the International Monetary Fund a plan to change Britain's debt rules that will open the door for the government to spend up to 50bn extra on infrastructure projects.

After weeks of speculation, the chancellor will confirm at the fund's annual meetings in Washington on Thursday that next week's budget will include a new method for assessing the UK's debt position - a move that will permit the Treasury to borrow more for long-term capital investment.