THE former head of the Civil Service offered yesterday to give a public rendition of God Save the Queen if Tory ministers dropped plans to curb trade union funding.

Sir Bob Kerslake, who is now a crossbench peer, made the unorthodox suggestion in a Lords debate over the Trade Union Bill.

The Bill includes the end of check-off, which allows public-sector workers to have their union fees deducted directly from their wages.

While the government claimed that scrapping the system would save taxpayers money and “modernise” industrial relations, Mr Kerslake said the check-off was convenient for workers and came at virtually no cost.

“I think it is impossible to see why any fair person would want to remove this very basic service provided to public service employees,” Mr Kerslake said.

“The real reason we have this proposal in front of us is in reality an unspoken one.

“The government do not like the public-sector unions and they want to make life a bit more difficult for them.

“I think this genuinely demeans the government.”

Public-sector union Unison said it could lose 800,000 members overnight if check-off was abolished.

Tabling an amendment to the Trade Union Bill seeking to protect check-off, Mr Kerslake urged Tory ministers to accept it by alluding to David Cameron’s criticism of Jeremy Corbyn’s dress sense.

“I am wearing a suit, my tie is straight and I am more than happy to sing the national anthem — or at least the first verse — if the government will think again,” he said.

Mr Kerslake may be saved however, as the Tories do not have a majority in the upper chamber and some of their own back benches are in rebellion over the issue.

Tory Baron Richard Balfe said: “I could be very rude about it. If there is a division I will be in the lobby against my own party.”

The Bill is likely to pass but key parts could be removed at report stage next month.

A report on government plans to introduce an opt-in political levy for trade unions is also expected to be savaged in a report due to be published on Monday.