SCOTTISH Labour leader Anas Sarwar is among the politicians to have defied UK party leader Keir Starmer’s instruction to keep away from the picket lines as rail workers go on strike.

Starmer, in a memo reported by PoliticsHome, ordered his frontbench team not to join the striking Network Rail workers.

The memo said: “We have robust lines. We do not want to see these strikes to go ahead with the resulting disruption to the public. The government have failed to engage in any negotiations.

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“However, we also must show leadership and to that end, please be reminded that frontbenchers including [parliamentary private secretaries] should not be on picket lines.

“Please speak to all the members of your team to remind them of this and confirm with me that you have done so.”

The news sparked outrage among the Labour membership and the trade union movement.

Sharon Graham, the general secretary of Unite the Union, said: “The Labour Party was founded by the trade unions and we expect Labour MPs to defend workers, by words and by actions. To instruct Labour MPs not to be on picket lines with workers speaks volumes.

“You don’t lead by hiding. No one respects that. It’s time to decide whose side you are on. Workers or bad bosses?”

Gordon Martin (below), the Rail, Maritime and Transport (RMT) union's Scotland organiser, condemned the order for UK Labour frontbenchers to stay away from the picket lines.

The National:

He told The National: “Keir Starmer should be sacked as leader and kicked out of the party as far as I’m concerned.

“These statements from Starmer have gone way, way beyond anything we’ve seen. [Tony] Blair used to boast about the UK having the most destructive anti-union laws in the western world. Starmer’s going steps further than that.

“He’s telling people not to support striking workers. He should be sacked as leader and kicked out of the Labour Party.”

READ MORE: Scotland's rail network grinds to a halt as workers walk out in mass strike

However, scores of Labour MPs announced their intention to support the strikers on the picket lines, which will be set up on at least June 21, 23, and 25.

Former shadow chancellor John McDonnell replied to Graham on Twitter: “Let me make it absolutely clear, I will be on the picket lines.”

Other figures from the left of the party expressed their support for the strikers, with Richard Leonard – the former Scottish Labour leader – heading to the picket lines in Glasgow on Tuesday morning.

Sharing a video of himself there, Leonard wrote: "It's a basic principle. You don't debate whether you back workers on strike or not."

Zarah Sultana, Diane Abbott, Richard Burgon, Rebecca Long-Bailey, Nadia Whittome, and Clive Lewis were among the other Labour MPs to publicly support the strikers.

Sarwar also expressed “solidarity” with those striking, sharing images of himself with workers protesting outside Edinburgh’s Waverley station.

The Scottish Labour MSP wrote: “Solidarity with those on the picket lines. This is a crisis entirely of the Government’s making.

“The workers don’t want strikes. The unions don’t want strikes. The public don’t want strikes. They demand better.”

Around 40,000 members of the RMT union at Network Rail and 13 train operators have walked out in a bitter dispute over pay, jobs and conditions.

While ScotRail staff are not involved, the UK-wide strike has impacted on signallers and other key workers, meaning only around 10-15% of trains out of Glasgow Central are running, according to staff.