Canada Post administrative and technical workers are on strike Monday after rejecting a final offer from their employer late last week.

Some of the first picket lines went up in Halifax, Antigonish and Sydney, N.S., and in Fredericton and Saint John, N.B. and St. John's, N.L.

The federal postal service maintains mail delivery will not be affected by the walkout of the 2,140 employees, the majority of which are based in Ontario.

Canada Post spokesperson John Caines said the striking workers represent about five per cent of the people working for the post office.

Caines told CTV.ca that the province-by-province breakdown of the striking workers is as follows:

• 263 in the four Atlantic provinces
• 264 in Quebec
• 1,224 in Ontario
• 132 in Manitoba
• 16 in Saskatchewan
• 115 in Alberta
• 124 in B.C.
• Two workers in the Northwest Territories and the Yukon

The striking administrative and support workers are part of the Union of Postal Communications Employees (UPCE), Caines said, while the people who sort and deliver mail for Canada Post are part of a separate union called the Canadian Union of Postal Workers (CUPW).

The details of disability and family-leave benefits in the proposed four-year contract are the main points of contention for the UPCE.

UPCE president Richard Des Lauriers told The Canadian Press that Canada Post has put forward a short-term disability plan that would replace current sick-leave credits and family-related leave provisions "that we've had for over 10 years."

Though Canada Post says mail delivery won't be affected, Des Lauriers suggested it will be eventually.

"We are planning to slow down the mail delivery and put pressure on the employers to return to the table with a decent offer to end this quickly," he told CP from the picket line at Canada Post headquarters in Ottawa.

In a statement, the federal corporation said its offer is rooted in the goals of maintaining the viability of Canada Post and preserving good jobs.

"Consistent with that theme, we believe this is a generous offer, given the current economic climate, that we hope will achieve a new collective agreement that meets the needs of both the employees and the company."

The proposal described by Canada Post as its "final offer" to the union included income protection for all employees, plus a 2.5 per cent salary increase in the first two years of the contract, and a further 2.75 per cent in the final two years.

Here are some further details of the four-year contract offer, as released by Canada Post:

• Job security for all indeterminate employees on strength at the time of contract signing.
• Premiums for night shift and weekend shifts will be increased from $1.15 to $1.40, and evening shift premiums will increase from $0.95 to $1.15.
• Special Leave to be used for urgent family situations, similar to that now available to other bargaining units.
• This is in addition to the seven personal days under the Short Term Disability Program.
• Retention of seven weeks for holidays after 28 years service for all employees at the time of contract signing.

As of mid-afternoon on Monday, Caines told CTV.ca that Canada Post had not yet received a response from the union.

Des Lauriers spoke to CTV.ca on Monday evening and said that he could not comment on the offer from Canada Post because he had not personally seen it yet.

The bargaining is being handled by UPEC's parent union, he said, the Public Service Alliance of Canada.

Des Lauriers said he expects that UPEC will meet with PSAC on Monday night to discuss the offer from Canada Post.