By Amanda Ferguson BELFAST (Reuters) - Northern Ireland's deputy leader, Martin McGuinness, resigned on Monday in protest at First Minister Arlene Foster's handling of a controversial green-energy scheme, a move likely to trigger an election in the British province. The collapse of the relationship between Irish nationalist leader McGuinness and Foster, a pro-British unionist, risks paralysing the region's response to Britain's planned exit from the European Union as London prepares to trigger divorce talks. McGuinness also raised the prospect of a lengthy renegotiation of the terms of power-sharing, part of the 1998 Good Friday peace agreement, saying there would be "no return to the status quo" after an election.
