Today, for the first time in more than three-and-a-half years, the North South Ministerial Council will meet in Dublin.

When the two administrations last held discussions in Armagh in November 2016, Enda Kenny was taoiseach, Frances Fitzgerald was tánaiste, Arlene Foster was first minister and Martin McGuinness was deputy first minister.

The gap was caused by the collapse of the DUP and Sinn Féin partnership at Stormont in January 2017 and the resultant absence of a devolved government for three years.

The restoration of power-sharing in Northern Ireland in January and last month's formation of a three-party coalition in Dublin allows for a rebooting of the North-South structure that was established as part of the Good Friday Agreement.

The two administrations face several complex, common challenges although some of their views on how to tackle them may differ.

The most pressing and the most difficult ones are the Covid-19 pandemic and Brexit.

Coronavirus

Unionist politicians in Northern Ireland instinctively take their lead from "the mother ship", Westminster (also the source of funding). Nationalists keep a close eye of the strategies of their neighbours across the porous land border.

The leaders of the Stormont administration, DUP First Minister Arlene Foster and Sinn Féin's Michelle O'Neill, disagreed at times over how to tackle the coronavirus issue. But a Stormont hybrid strategy, involving some elements of the London and Dublin policies, has managed to give Northern Ireland the UK's lowest disease numbers.

Policy in relation to foreign travel and the different regulations and advice in place North and South of the border will be key issues under discussion in Dublin today.

At present, compared to what applies in the South, Northern Ireland travellers are allowed to but not encouraged to travel to a significantly greater number of foreign destinations.

Irish travellers are allowed to cross the Irish Sea with no restrictions in place when they arrive in Britain. This arrangement is consistent with the UK/Ireland Common Travel Area principles. But there is no quid pro quo arrangement. Travellers making the opposite journey are expected to restrict their movements for 14 days after they arrive in Ireland.

Individuals who indicate they are heading to Northern Ireland after they arrive in Dublin can avoid the 14-day provision.

There is significant evidence of the anomalies being exploited and Northern Ireland being used as a wide-open back door. A number of Stormont ministers say they want to see more exchange of information between the administrations in relation to visitors and other passengers arriving onto the island.

Maybe the timing is a coincidence, or maybe it runs deeper, but Northern Ireland has just introduced a Virus Mobile Phone Virus Tracker App. First indications suggest it will allow for some sharing of information on both sides of the border.

Today's discussions won't produce an agreement for full harmonisation of Covid-19 policies between Dublin and Stormont. But there will be very definite endorsement of the need for ongoing, close co-operation. Yesterday's confirmation of 85 new cases of the disease, south of the border, has confirmed fears that the battle against the virus is not over. Northern Ireland reported eight new cases.

Brexit

Brexit is the other hugely significant challenge that is gathering momentum.

The island of Ireland cannot avoid being affected by the consequences of the UK leaving the European Union on 31 December.

In a benign setting, involving Boris Johnson's administration reaching a comprehensive trade agreement with Brussels before it formally relinquishes its EU membership, Northern Ireland could develop a pick and mix EU/UK relationship, in the same way that it has developed its hybrid Covid-19 strategy.

But if the UK leaves with no deal, the immediate economic consequences for the island of Ireland could be much more severe. The delicate, nuanced North-South and East-West relationships, nurtured in recent years, could come under strain.

Micheál Martin's "shared island" philosophy, including the unit being set up in the Department of An Taoiseach, would fit comfortably within a healthy EU/UK post-Brexit relationship.

There has been no face-to-face meeting between the Taoiseach and Boris Johnson since the Fianna Fáil/Fine Gael/Green Party coalition was formed. That may change very soon.

A difficult month

The two administrations have struggled through a difficult month. Micheál Martin is leader of a Fianna Fáil party not used to the challenge of government. Tánaiste and former taoiseach Leo Varadkar is good. But sometimes too good for his own good and the coalition's good? The Green Party is, at times, in NGO (non governmental organisation) mode.

Michelle O'Neill's tough stance on tackling the coronavirus problem was undermined by Sinn Féin's involvement in Bobby Storey's funeral. After a solid phase, just this week Arlene Foster's ability to heed warning bells came into sharp focus after policy disagreements within her own DUP party.

The hosts and the visitors will welcome the opportunity to find some common ground and do some productive work today.

The podium arrangers for the post-meeting news conference will have a challenge this afternoon. Make space for Taoiseach Micheál Martin, Tánaiste Leo Varadkar, Northern Ireland's First and Deputy First Ministers, Arlene Foster and Michelle O'Neill.

But will Eamon Ryan, the Green Party leader, be there? And what about the Minister for Foreign Affairs, Simon Coveney, who has the most regular interactions with Northern Ireland?

Or will four be the full house?

One thing is sure - Mary Lou McDonald, Sinn Féin's president and leader of the Opposition, won't feature.