Q&A: What has caused the Stormont powersharing crisis and can it be resolved?

The powersharing crisis at Stormont has run for 10 months. As the parties face yet another deadline day, here are the answers to some of the key questions about the bitter political stand-off.

Q. Another deadline?

Yes, the fifth since powersharing imploded in January. Despite Government warnings of the consequences of missing the previous cut-off points for a deal, they all fell by the wayside. The elasticity of the time-limits has led to widespread public scepticism over their credibility.

Q. Is this one different?

Northern Ireland Secretary James Brokenshire has repeatedly made clear that if there is no agreement by Monday he will intervene to set a budget for Stormont's rudderless public services. While this will not constitute the reimposition of Westminster direct rule, it is a large leap in that direction. Civil servants have warned that the money will dry up and key services will be disrupted if a budget is not enacted in the coming weeks, so it seems inevitable one will be passed, with or without the say of local politicians.

Q. Mr Brokenshire keeps talking about his "glide path". What is that all about?

The Secretary of State has employed this analogy to explain his approach to increasing Westminster authority over Northern Ireland. The longer the crisis goes on, the closer Stormont gets to touching down on the runway of direct rule. He envisages powers being taken on by London in gradual fashion, rather than a sudden crash landing. The passing of a budget will certainly see the landing lights looming large on the horizon.

Q. Stormont collapsed amid a row over a botched green energy scheme, so how come a row over the Irish language is preventing it being restored?

The controversy over the Renewable Heat Incentive (RHI) triggered the implosion of the last Sinn Fein/DUP led coalition. The ill- fated eco subsidy scheme left the administration facing a potential £500 million overspend and the late Sinn Fein deputy first minister Martin McGuinness quit the executive - a move that pulled it down - in protest at the DUP's handling of the furore. It was ironic that the issue that toppled the coalition of erstwhile foes was a financial scandal, and not one of the deep-rooted orange and green disputes. However, once the government went up in RHI smoke, a non-aggression pact that had marked the DUP/Sinn Fein relationship was well and truly kicked into touch and many of the old wounds were reopened. The one that has proved most troublesome to heal is the stand-off over Irish language.

Q. So what is the row about?

Sinn Fein want a piece of legislation that enshrines protections for Irish language speakers, such as the right to speak Gaelic in court proceedings and more widespread use of bilingual road signs. The DUP is prepared to offer some protections but only if they are part of a wider cultural act, which also takes in the Ulster Scots tradition. The row essentially boils down to whether or not there will be a free-standing Irish Language Act.

Q. Are there other issues dividing the parties?

Yes, Sinn Fein and the DUP are at odds over the region's ongoing ban on same sex marriage. The pro-Brexit DUP and pro-Remain Sinn Fein obviously have very different takes on the UK's exit from the EU as well. Stalled mechanisms to deal with the legacy of the Troubles is another source of contention. But there is a growing view that none of these would, in themselves, prevent an executive being formed. It seemingly all hinges on the Irish language.

Q. And RHI is not even a factor any more?

A public inquiry into the affair is about to start at Stormont. Sinn Fein had said it would not return to an administration that had DUP leader Arlene Foster as its first minister until she was cleared by the inquiry. That will not happen anytime soon, with the probe expected to run until next Easter. However, the longer the Stormont impasse has continued the less RHI has been mentioned. Many believe Sinn Fein would be prepared to drop the pre-condition on Mrs Foster if it got an Irish Language Act.