UPDATE 3-S.Africa council workers strike threatens services

* Council workers to strike from Monday

* Chemical union says new offer still below its demand

* Telkom, rail workers may also protest

* Increases pressure on govt after service protests

(Adds details, analyst comment)

By Gordon Bell

JOHANNESBURG, July 24 (Reuters) - South African council workers are to strike from Monday, unions said, threatening public services after several days of unrest in townships over poor housing and unemployment.

A chemical sector union was also considering on Friday an improved pay offer to end a strike while transport workers at the national rail operator are to decide on Monday whether to take industrial action.

Gold and coal unions will announce on Tuesday whether they accept an improved wage offer. If they reject it, stoppages will hit some of the world's biggest mines.

The strikes in Africa's biggest economy have increased pressure on new President Jacob Zuma, who rose to power with union backing, but have had little impact so far on markets.

But analysts have said this could change if strike action became more widespread. Zuma said police will move swiftly to crack down on rioters after violent protests erupted this week over poor services and the lack of jobs.

The South African Municipal Workers Union (SAMWU) and Independent Municipal and Allied Trade Union (IMATU), which say they represent 150,000 council workers, said they had rejected an 11.5 percent wage increase.

"We can confirm the strike is going ahead on Monday. Both unions have a mandate to strike. We will only rescind that strike call when there is any offer from management," SAMWU spokesman Stephen Faulkner said.

He said union officials planned to meet Cooperative Governance Minister Sicelo Shiceka. "We are hopeful there will be some outcome and we can then put that to our members early next week (but) the strike is definitely going ahead."

A strike could mean refuse and transportation workers, licensing officers and city police staying at home. Johannesburg's council said it would make contingency plans to ensure minimal disruption to services.

NO AGREEMENT

The country's unions helped propel Zuma to power in an April election on a pro-poor platform. Instead of an expected cosy relationship, though, they are using their most powerful weapon -- strikes -- to press their agenda when South Africa is in its first recession in nearly 20 years and job losses are rising.

"Industrial strikes are a part of any free labour relations system. If you have the kind of economic conditions we have at the moment, it is going to last some time," political analyst Steven Friedman said.

A strike affecting the chemical, pharmaceutical and paper sectors, which began on Monday, may stretch into next week despite improved offers from employers.

The Chemical, Energy, Paper, Printing, Wood and Allied Workers Union (CEPPWAWU) said drugs sector employers raised their offer to an asked-for 10 percent rise but refused all other demands, including more maternity leave.

African Oxygen (Afrox), (AFXJ.J) Africa's biggest gas and welding firm, said it was monitoring the impact of the strike on its customers while it awaited the union's response.

Affected companies also include South African petrochemicals group Sasol (SOLJ.J) and chemicals firm Omnia <OMNJ.J.

Telecoms group Telkom (TKGJ.J) could also be hit by a communications workers' strike. "We will give Telkom a 48-hour notice to strike on Monday," said Gallant Robert, general secretary for the Communications Workers Union. (Additional reporting, Gugulakhe Lourie, Agnieszka Flak and Alison Raymond; editing by Robert Woodward)