By Brian Feeney Political commentator in Belfast

For the SDLP the results suggested in the opinion poll commissioned for BBC NI's Hearts and Minds programme must be as shocking as one partner in a stable relationship being dumped without warning.

It seems that while UUP ministers were happy enough to share power with the SDLP, their voters are not.

Not unexpectedly, since their ministers never sat at the executive table, 80% of DUP voters would not share power with either the SDLP or Sinn Fein.

But for Mark Durkan to discover that 37% of UUP voters want to dump him and that 58% of all unionist voters oppose power-sharing, suggests that in the future even a marriage of convenience is unlikely.

The polarisation of the two communities which observers have been describing during this year is vividly illustrated in the poll which not only shows the highest ever unionist opposition to the Good Friday Agreement at 67%, but also the lowest ever nationalist support for it at 82%.

'Agreement non delivery'

Clearly the Agreement had not been seen to deliver for either community.

Even for nationalists - who had set so much store by the Agreement that 96% supported it in 1998 - now 54% would be prepared to renegotiate it.

Mark Durkan trailing in the popularity stakes

On the bright side, that seems to indicate a nationalist readiness to accept an historic compromise, but with whom? If unionists are overwhelmingly opposed to the Agreement that means they oppose it in any shape or form.

Unionists instead prefer direct rule, while less than 4% of nationalists find it acceptable.

A clear majority of nationalists want the assembly restored immediately, while less than 6% of unionists do.

Changing voter preference

These diametrically opposed opinions on the form of government for Northern Ireland are reflected in voter preferences which are more bad news for the SDLP.

For the first time ever Sinn Fein has come out ahead of the SDLP in an opinion poll. Sinn Fein with 19.6% to the SDLP's 17%.

This finding is especially significant because psephologists have always taken into account the tendency of respondents to understate support for Sinn Fein. On this basis Sinn Fein's support is likely to be even higher.

The same has always been true for the DUP which has also had a very good showing at 20.5% to the UUP's 22.5%. Among young people, both unionist and nationalist the gap is even wider.

Support for the Alliance Party at 3% is vanishingly small in a poll with a 3% margin of error.

Most disconcerting for the SDLP and the Irish and British Governments will be the finding that, among nationalists, as a whole Gerry Adams outpolls Mark Durkan 41% to 35%.

Even among SDLP voters 15% of them prefer Gerry Adams and Martin McGuinness to their own leader, Mark Durkan.

In short, when Sinn Fein and the SDLP examine the findings of this poll they may have to re-think some basic tenets of their long term policies.

If a decisive majority of unionists don't want partnership at any price why bother struggling to reconstruct the assembly?

Why make concessions to unionists before an election if unionist voters are likely to reward the party spurning the concessions?