Any trade union which chooses to defy "draconian" new laws affecting their rights will have the full support of the Scottish Trades Union Congress (STUC), an anti-austerity rally has heard.

Dave Moxham, deputy general secretary of the STUC, said the UK Government's Trade Union Bill was directly linked to the Conservatives' austerity agenda.

He told a meeting of the non-partisan anti-austerity campaign group, the People's Assembly, that his organisation will back any unions who defy its measures if they are passed into law.

The Bill will curtail the amount of time members can spend on union duties at work, known as facility time, and end union subs 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.

Speaking at the Glasgow rally, Mr Moxham said the fight against the Bill was also an opportunity to grow the trade union movement, and take 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.

"Now 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 to build the trade union movement.

"We do face real challenges, we do face an enormous attack upon trade union capacity...but we also have a real opportunity.

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