IT remains unclear how many of the SNP's Westminster MPs in London will stand with activists outside the Supreme Court and at rallies across Scotland on Wednesday – as judges issue their ruling on an advisory second independence referendum.

UPDATE: MPs are in the courtroom and it remains unclear if guidance was issued by SNP HQ.

Only four of the party's MPs are confirmed to be taking the roughly five-minute walk to represent Scotland and join Yes London activists.

Several MPs have prior commitments at debates and house business but most, The National understands, are waiting for guidance to come from HQ.

READ MORE: How The National will be covering the Supreme Court's indyref2 ruling

SNP MP Angus MacNeil, who has committed to heading to the court for 9:45am, said: “Doubtless a good number of Scots and a good few pro-independence MPs will be there for an historic moment to kick start next stage to independence.”

He will be joined by MPs Douglas Chapman, Brendan O’Hara and John McNally.

At the main rally in Edinburgh, SNP MP Tommy Sheppard and Alba MP Neale Hanvey will speak to the expected crowd of 5000 or more.

One senior SNP source described the party’s commitment and support for grassroot efforts as “lukewarm”.

Another party source said it is “disappointing the lack of understanding of the moment or general enthusiasm”– and the lack of guidance from party officials means some individuals and groups are wary of committing to efforts.

Activists will appear at a total of 19 rallies – 15 in Scotland, two in England, and six in Europe – no matter the decision.

Earlier in the week, SNP policy development convener Toni Giugliano kicked off the call for members to join the rallies.

He said: “I’m keen to ensure the SNP put some weight behind these rallies. I understand why there is a hesitancy to not attend these unless the SNP organises them, but I think unless we do, they are organised without us.”

READ MORE: Alex Salmond to speak at Inverurie rally over Supreme Court verdict

Kirsteen Fraser, SNP equalities convenor, joined Giugliano in calling for action by the SNP to support the rallies.

She said: “We’ve been reticent in the party about engaging with rallies, protests, and demonstrations since 2014 to the point it can look like we have abandoned the field.

“It is time for us to be brave, bold, and visible across all spheres in public life about Scotland’s right to decide.”

The SNP were approached for comment.