The "bitterness" is that the UK has, in diplomatic language, suggested it could revoke the Ecuador embassy's status in order to enter the premises and fulfil the arrest warrant. This is not the oh-so-dramatic "storming the embassy" rhetoric that was put out, and any such intention would be legally challenged and end up in lengthy litigation as the UK's 1987 act went up against relevant international law.
However it does represent an escalation of the situation, and one which could see the sanctity of diplomatic missions in troublespots around the world put under increasing threat. It would be a very dangerous move on the UK's part to try and enforce extradition in this manner.
It is only the Ecuadorans who have claimed that Britain has threatened to storm the embassy and ''savagely beat'' the people inside. And of course they haven't, but a lot of people seem to want to believe this.
I read the conditions that Ecuador agreed to, and Britain has the right to revoke the status of the embassy, in the event that the building is used for other than consular business. It is not something made for Ecuador, it is normal procedure. If the embassy status was revoked, then it would not be extradition.
BREAKING NEWS: Brits just released a statement that they are committed to a negotiated settlement. How disappointing for the rabble.