Scotland is staying. London's headaches are just starting.

British leaders are relieved by the Scots' vote against independence. But devolving new powers to Scotland – and perhaps to England – may be a bigger challenge for Westminster than the referendum was.

The Scots have voted no to independence. But their majority decision has raised more questions than answers about the future of the United Kingdom.

While the Scottish National Party takes stock and anticipates new powers for the Scottish parliament at Holyrood, constitutional experts and campaigners are trying to interpret Prime Minister David Cameron’s victory speech and what it means for England, Scotland, Wales, and Northern Ireland.

Mr. Cameron spoke of a "new and fair" constitutional settlement which would answer the politically thorny issue of "English votes for English laws."

Under the current system, many areas like health, education, and environment issues are devolved to the parliaments of Northern Ireland, Wales, and Scotland. However those countries’ Members of Parliament can still vote on the issues even when they only affect England, which makes up 84 percent of the UK population.

Eddie Bone from the Campaign for an English Parliament says he was disappointed by the Scottish vote, because a yes would have put more pressure on British leaders to grant some form of English self-rule.

But he says Cameron’s comments and the Scottish "Yes" campaign have made change inevitable. “We have to have a first minister, an executive, and a minister for England. We don’t accept what some of the national politicians like Nick Clegg have been suggesting that we devolve power to the regions and big cities."

Such a move, he argues, "will lead to the breakup of England and ultimately the UK. There has to be fairness first, and you don’t do that by dividing cities and regions.”

Cameron has assigned the Leader of the Commons and former foreign minister William Hague to chair a committee to examine the anomaly of Scottish, Welsh, and Northern Irish MPs voting on English matters. But he also warned that if no agreement was reached, it might have to be decided after next year’s general election.

The three main British parties pledged before the referendum to devolve more powers to Scotland in the event of a no vote, maintaining a controversial formula by which Scotland receives more public spending per head of population than other constituent parts of the UK.

Breaking 'the vow'

But constitutional expert Iain McLean at Nuffield College, Oxford, says he is skeptical about the parties' promise, dubbed "the vow."

“It was a panic measure and I think Cameron is going to have difficulty seeing it through," Professor McLean says. "On the day of the referendum, we saw his own MPs saying no more financial powers, which was extraordinary for members of what is the Conservative and Unionist party to be saying at such a sensitive time."

But while politicians south and the north of the border absorb the result, "Yes" campaigners acknowledge they have lost a chance of a generation to achieve independence.

One of the more unusual groups was English Scots for Yes. Co-founder Math Campbell, who was born and raised near Cambridge but moved to Scotland at 18, says the result has been tough. He blames the "British establishment" for his campaign's defeat. “I hope they do follow through on the vow but I’m not sure it’s deliverable. We managed a huge swing in support with 1.5 million people wanting independence but it wasn’t enough."

“The establishment had to wheel out big business – the banks, supermarkets – to frighten people which helped put people off,” Mr. Campbell says.