There are two sets of sanctions which I understand the government is preparing in response to different outcomes in Ukraine. There are the wide-ranging sanctions which will be brought to bear should President Vladimir Putin launch a full-scale invasion.
This would include limiting access to sovereign debt and foreign exchange markets, restricting technology exports and of hitting more oligarchs, banks, defence and energy companies.
And then there is a second, more limited, list of sanctions which would be added to the current sanctions regime if President Putin doesn't doesn't back down from his current position.
But as things stand people at the top of the Foreign Office don't think they're going to be needing the second list.
Foreign Secretary Liz Truss said this morning that she believes Vladimir Putin is 'hell bent' on the invasion of Ukraine.
But putting the wide-ranging sanctions in place doesn't seem to be proving easy.
The UK has placed asset freezes and travel bans on five banks and three oligarchs.
But government lawyers are still working through the legalities of putting more sanctions on all the Duma deputies who voted to recognise the rebel regions of Luhansk and Donetsk - giving President Putin an excuse to send in 'peacekeeping troops'.
Then there are the cultural sanctions which the government would clearly like to see; removing the Champions League Final from St Petersburg and doing something about Russia Today.
In different ways these aren't in the government's gift. The football final is up to UEFA, although given the pressure on them from the prime minister and others it would be surprising if they didn't move it.
And the Russia Today licence is an Ofcom issue.
The government doesn't want to get into the business of banning TV stations itself and so the culture secretary has written to the regulator outlining her "concerns" with the station. So the sanctions regime is very much a work in progress, even as it is being put into action.