What is the dialling code to phone London from Philippines?

Philippines country code is +63.

From London, dial 00 63 then the full Philippines number minus any leading zero.

If calling a London landline number from the Philippines dial 00 for international access, 44 for the UK, 20 for London, then the 8 digit London number.

If calling a UK mobile number from the Philippines dial 00 for international access, 44 for the UK, then the 10 digits of the mobile number (beginning with a 7).