Yesterday's fresh offer from the government on public service pensions followed intense behind-the-scenes work and lobbying with officials and ministers, with Prospect playing a key role.

The government would not have moved without the determination of Prospect members, who made thousands of representations to employers, MPs and the Cabinet Office against the original proposals, said Prospect deputy general secretary Dai Hudd.

He added: "The move to ballot on industrial action, along with other public sector unions, has also had a profound effect on ministers.

"It is vital to sustain the pressure without let-up until the pensions issue is concluded on a basis that is acceptable to members. So please vote yes in the ballot and ask your colleagues to do likewise."

At the same time, negotiations will continue with a view to reaching a resolution. For the civil service and other schemes many details need to be clarified, and many difficult issues ironed out, said Hudd. "It is therefore too early to indicate how this will affect the negotiations. Although most of the changes are helpful, as yet we have no offer to put to members on the design of the new scheme, which is obviously crucial.

"We will be working hard to try and arrive at this point in the next few weeks and will deliver a detailed report on developments at a major seminar for Civil Service representatives on 15 November."

One potential fly in the ointment is that the offer is conditional on agreement being reached in the individual scheme talks by the end of the year. It should be noted that the Chief Secretary did not say it was conditional on the 30 November day of action being called off, as erroneously reported in some media.

The government's revised proposals were presented at a meeting between the TUC and ministers attended by general secretary Paul Noon, along with other public sector union leaders.

After the meeting, the TUC's Public Sector Liaison Group received a report of the discussions and copies of the letter setting out the proposals, and issued a statement.

Hudd said: "Discussion at the TUC broadly welcomed these moves by the government, and recognised they were a significant step forward.

"However, the changes fail to address many of the problems associated with the cut in the value of benefits due to the CPI switch, increases in employee contributions during the pay freeze, and the planned increases to pension age.

"It was therefore agreed that scheme discussions should commence on the basis of the new offer to explore what potential impact they will have and the scope for further improvement."

Hudd added that all the unions regretted that it had taken the government until now to improve its offer.

See the main points of the government's offer here.