Sinn Fein's Martin McGuiness was NI deputy first minister 10 Jan
Martin McGuinness has resigned as Northern Ireland's deputy first minister in protest against the handling of a botched energy scheme that could cost taxpayers £490m.
The decision to quit is likely to lead to a snap election in NI.
It's a story that's been breaking since last night and its impact on the stability of NI politics and the "peace process" can not be underestimated.
The BBC has more here
Given that NI is part of the UK there is a knock-on effect too and PM May will not be wanting to be de-railed from all things Brexit.
The pound's continued weakness in Asia will have been related to some degree.
GBPUSD currently 1.2150 after 1.2136 lows. EURGBP 0.8730 from 0.8737 and still underpinned.
I continue to play GBP from the short side.
Martin McGuiness - A political decision to resign
