Thousands of Scottish public sector workers have joined a UK-wide walkout as they demand an increase in pay.

Court services were reduced and museums and driving centres closed as members of the Public and Commercial Services (PCS) union protested over what it has calculated as a 20% cut in earnings through a pay freeze and cap in recent years.

Civil servants, council staff and cleaners stood on picket lines across the country, and rallies were held Glasgow and Edinburgh.

The PCS in Scotland said the 24-hour strike had enjoyed large support as people called on ministers to "break with the imposed UK austerity pay cap" in the run-up to the independence referendum.

The union said there was only one courtroom in operation at Edinburgh Sheriff Court - the best strike turnout since 2011 - while Portree and Dingwall courts were closed completely.

The Scottish Court Service (SCS) said an estimated 26% of its staff were taking part in the industrial action.

PCS spokeswoman Joy Dunn said: "There has been disruption at the Scottish Government and a picket at the Scottish Parliament. More than 120 people joined the rally in Edinburgh.

"It's been very, very positive from our point of view. We've had a fantastic response from our members in Scotland."

The action follows a national PCS ballot which gained 73.7% support from its members. The union represents around 28,000 workers in Scotland.

A Scottish Court Service spokeswoman said: "There is a reduced service at some Scottish courts, while two courts are closed.

"Contingency plans are in operation and all essential court business is being dealt with. Emergency contact numbers are available for the public at all courts where a public counter service is not operating.

"Papers due to be lodged today will be accepted tomorrow, while most fines can be paid on our website."

The National Museum of Scotland and the National War Museum in Edinburgh were also shut due to the action.

A statement said: "These circumstances are entirely outside of our control and we apologise for the inconvenience caused to our visitors. The museums will open as normal on Friday July 11."

Members of the PCS national executive committee addressed members at rallies at the Mound precinct in Edinburgh and on Glasgow's Buchanan Street.

The PCS said 97% of all members working for the employment tribunals service at the Eagle Building in Glasgow went out on strike and Peterhead and Fraserburgh driving centres were shut.

Scottish secretary Lynn Henderson said: "John Swinney (the Scottish Finance Secretary) doesn't need to wait for the referendum to break away from (Chancellor) George Osborne and the pay policy of the Tories.

"At any point in the last seven years he could have rejected a below inflation pay cap and accepted the arguments of PCS that investment in public services, in public sector jobs, in fair pay for civil servants that would help Scotland's economy and help the way out of recession.

"Instead the people who work hard delivering Government priorities have faced the devastating consequences of losing thousands of pounds from their household incomes as their pay has been frozen or capped and inflation has eroded their day to day living standards.

"Our members will not sit back and watch public services being bled by austerity cuts. We will fight for jobs, decent pay, fair pensions and for properly funded public services for the people of Scotland."

A Scottish Government spokesman said: "As a result of the UK Government's austerity measures, the Scottish Government's discretionary budget is being reduced in real terms by 10.7% over five years. We have consistently rejected the Chancellor's approach to public finances and remain concerned about the impact of spending cuts on public services, household budgets and economic recovery.

"Within tight current budgetary constraints, we have set out a distinctive pay policy for Scotland that aims to be fair and affordable. In contrast to the UK Government, Scottish ministers' pay policy targets support for those on the lowest incomes, including a commitment to the Scottish Living Wage and a minimum pay increase above 1% for those earning less than £21,000.

"PCS has called on its members to take part in strike action on July 10 as part of a UK wide dispute over pay, pensions and terms and conditions. This action has been planned since May 30 2014, and therefore is not connected to the outcome of pay negotiations within the Scottish Government."