considers

Ehhh...The closest analog to the US removing Maduro actually probably happened when Thatcher was in office, Grenada.

https://en.wikipedia.org/wiki/United_States_invasion_of_Grenada

The United States and a coalition of Caribbean countries[a] invaded the island nation of Grenada at dawn on 25 October 1983. Codenamed Operation Urgent Fury by the U.S. military, it resulted in military occupation within a few days.[9] It was triggered by strife within the People's Revolutionary Government, which led to the house arrest and execution of the previous leader and second Prime Minister of Grenada, Maurice Bishop, and to the establishment of the Revolutionary Military Council, with Hudson Austin as chairman. Following the invasion there was an interim government appointed, and then general elections held in December 1984.

The invasion drew criticism from many countries. British Prime Minister Margaret Thatcher privately disapproved of the mission, in part because she was not consulted in advance and was given very short notice of the military operation, but she supported it in public.[10] On October 28, 1983, three days after the invasion, the U.N. Security Council by a vote of 11 to one failed to pass a resolution "deeply deploring" the invasion, calling it a "flagrant violation of international law" (the United States vetoed the resolution).[11]

Grenada is part of the Commonwealth of Nations and the intervention was opposed by several Commonwealth members including the United Kingdom, Trinidad and Tobago, and Canada.[1]: 50  British Prime Minister Margaret Thatcher, a close ally of Reagan on other matters, personally opposed it. Reagan had forewarned her it might happen; she did not know for sure that it was coming until three hours before. Although she publicly supported the action, she sent the following message to Reagan at 12:30 on the morning of the invasion:

This action will be seen as intervention by a Western country in the internal affairs of a small independent nation, however unattractive its regime. I ask you to consider this in the context of our wider East/West relations and of the fact that we will be having in the next few days to present to our Parliament and people the siting of Cruise missiles in this country. I must ask you to think most carefully about these points. I cannot conceal that I am deeply disturbed by your latest communication. You asked for my advice. I have set it out and hope that even at this late stage you will take it into account before events are irrevocable.[87][88] (the full text remains classified).

Her complaints were not heeded, and the invasion continued as planned. While the fighting was still going on, Reagan phoned Thatcher to apologize for any miscommunication between them,[89] and their long-term friendly relationship endured.[90][91]

That being said, it very much sounds to me like Starmer wasn't notified in advance, and I can't imagine that he'd make any strong statements without consulting with the Foreign Office, the US, and probably some other countries as well. Probably put together some kind of British position over the next several days, if I were to guess. He also said something more-or-less to that effect, that he'd need to communicate with the US and some other countries on the matter.

Nah, you are all right thanks. I'd rather have someone who takes a bit of time to make a decision than Margaret fucking Thatcher. What the fuck?