Trade unions are being urged to defy 'draconian' new laws affecting their rights.

The Scottish Trades Union Congress (STUC) has offered its full support to those opposing the UK Government's Trade Union Bill.

Dave Moxham, deputy general secretary of the STUC, told an anti-austerity rally in Glasgow that the bill was linked to the Conservatives' austerity agenda.

The bill will curtail the amount of time members can spend on union duties at work, known as facility time, and end union subscription fees coming off pay at the point of pay roll, a practice known as check off. Employers will also be able to bring in agency workers to cover for strikers.

Mr Moxham told a meeting of the non-partisan anti-austerity campaign group, the People's Assembly, that the fight against the bill was an opportunity to opposition to the Tory government "to a whole new level".

He said he also hoped that progress would be made in securing a legislative consent motion (LCM) for the Bill at Holyrood when it is debated by MSPs on Tuesday.

The Scottish Parliament's Presiding Officer rejected an attempt to get an LCM tabled - a move which would allow MSPs to vote against it.

"If this piece of legislation comes in, then people will want to know what the trade union movement is going to do about it," Mr Moxham said.

"It is not my job as a representative of the STUC to tell unions what they should do when faced with these draconian laws, but it is my job to say this: any trade union that chooses to defy any aspect of this law, whether it is the picketing requirements, whether it is the ballot requirements, whether it is any aspect of this law, will have the full support of the STUC if they choose to do that.

"We also say we have used this as an opportunity to build the movement, because if we can say that the Tories' intention is to attack our capacity to oppose them on the streets, to oppose them politically, then we need to redouble our efforts.

"We have a real opportunity to build the trade union movement, to take our opposition to the Tory government to a whole new level."

SNP MP Chris Stephens also addressed the rally.

He said: "The SNP will continue to do everything we can in government and at Westminster to oppose the Tories' austerity agenda.

"The devastating cuts that the Tories are making across the UK - including to Scotland's budget - are an austerity of choice not necessity and we have seen the damage it is doing to our communities, our public services and the economy.

"At the Scottish Parliament elections in May we have an opportunity to reject Tory austerity and re-elect an SNP Scottish Government that will stand up for Scotland."

Labour MSP Elaine Smith told those gathered that the austerity agenda and measures such as the Trade Union Bill were "not inevitable".

"The People's Assembly and our comrades across the Labour movement have shown that if we organise we can oppose these attacks, and we can demand alternatives," she said.

"While the Tory government outright supports austerity and attacks our class, the SNP claims to oppose these attacks, but they don't deliver on their promises and they cloud the issues.

"Now, more than ever, we need people power to ensure that our governments both here and at Westminster are made to listen and act in the best interests of the many and not the few."