Alex Younger had been due to retire in November after leading the organisation for five years

The head of MI6 is expected to stay in post beyond his retirement date this year to guide the secret intelligence service through the post-Brexit period, The Times has learnt.

Alex Younger, 55, is due to retire in November after five years in the role. Whitehall officials want him to extend his appointment to cover the 12 to 24 months after Britain has left the EU.

If Theresa May and Jeremy Hunt, the foreign secretary, confirm the extension, he will become the longest-serving MI6 chief since the 1960s.

No formal decision has been made. However, Whitehall sources said that it was crucial for the heads of the security and intelligence services to stay unchanged during the period of upheaval after leaving the European Union.