More than 20 Orange Order parades will be staged in Glasgow this weekend, as its members and thousands across the city commemorate the Queen's 60 years on the throne.

Following two city marches on Saturday, the Orange Order will parade from the north, south, east and west of Glasgow and congregate in the city centre this Sunday, as a large number of lodges celebrate the Diamond Jubilee.

In all, there will be 20 separate processions coming into and leaving the city across late morning and afternoon, with a service at the Evangelical Church in Cathedral Square on High Street as part of the annual County Church Parade.

Some of those taking part are doing so specifically to commemorate the Jubilee. Further Jubilee parades are expected in Glasgow across the summer.

Around 1500 members of the organisation will take part in the parades, with thousands expected on the streets to watch the event.

There are no police objections to the timings or the routes of the parades, which will cause some congestion and delays for shoppers and travellers. Most major routes into the city centre will be impacted from around 2pm and again at 5pm.

Following concerns in recent years over the impact on policing costs, the Orange Order now picks up the tab for stewarding its own major events in the west of Scotland, with police presence scaled down.

After the annual Boyne celebrations in July, it is expected to be the biggest Orange event going through the city centre in 2012. Sister organisation, the Royal Blacks, have a major event on August 11.

It has also emerged that most of the eight official street parties taking place in Glasgow between Saturday and Tuesday are being run by the Orange Order or are in the immediate vicinity of the local Orange Hall.

The parties in Possil, Springburn and Pollokshaws are being run by the organisation, while those in Govan and Bridgeton are alongside the lodges.

Just over 100 street parties celebrating the Jubilee are planned for Scotland, while an estimated 9500 are expected in England and Wales.

Edinburgh has more than 30 parties confirmed, while the Borders is spending around £40,000 on various events.

Meanwhile, opposition politicians in Glasgow are boycotting taking seats on a body that decides on controversial marches over plans to overhaul the city's approach to parades.

As Glasgow heads into the "marching season", The Herald understands that even members of the Labour administration have been reluctant to take seats on the public processions committee, with one claiming: "It's a committee to avoid at all costs."

Earlier this month it emerged the leader of the city council, Gordon Matheson, told a pre-election meeting with the Orange Order that his authority's landmark policy on limiting the number, routes and timings of parades was "wrong" and promised to overhaul it.

The SNP has now said that as long as it remains unclear as to the direction the council wants to take the policy, which has been lauded by police chiefs as a template for the rest of the Strathclyde area, they will not take positions on it.

Graeme Hendry, leader of the council's SNP group, said: "At the moment, following councillor Matheson's comments, the parades' policy is up in the air. SNP councillors are more than happy to play a full part in the running of all council committees but we cannot do that on this occasion until we know what it is we're implementing."

Co-leader of the Greens, Nina Baker said that if offered her party would have taken a seat on the committee but would want further reductions in the number of parades. She added: "If there is a review in the offing we absolutely want to have our views known."

The public processions committee only meets when the police lodge objections to routes, the timing or nature of a parade, with the council then deciding how to act on the concerns.