The costs of modernising the F-35 warplanes could run to more than £12 billion

Britain will have to pay part of an estimated £12 billion bill for upgrades to the F-35 warplane over the next seven years to make it combat capable, according to comments made in the US.

A member of the House of Representatives armed services committee said that the modernisation costs to 2024 would be split between $10.8 billion (£7.8 billion) for software development and $5.4 billion for deploying the updates and other procurement issues.

Niki Tsongas was speaking after a sub-committee received a briefing from Vice Admiral Mathias Winter, head of the F-35 Joint Program Office, which oversees the project on behalf of the United States and nine other countries including Britain that are partners in the procurement. International customers were estimated to be responsible