(Updates status of talks, background)
OSLO, April 2 (Reuters) - Norwegian industrial workers and their employers continued to negotiate more than nine hours after a midnight deadline had passed on Wednesday in an effort to avoid strike action that would hit around 125 companies, many of them serving the country's vital offshore oil and gas industry.
If the state-mediated talks break down, more than 11,000 workers will immediately go on strike and could be followed by thousands more in the coming days and weeks.
Oil service firms Aker Solutions, Kvaerner , Aibel, WorleyParsons, Nexans and National Oilwell Varco are among the companies that would be hit from the start.
"We are continuing the work as long as necessary, as long as the parties want to," Nils Dalseide, the state-appointed mediator, told reporters.
Union and employers hold major wage negotiations every second year and oil workers went on strike for more than two weeks in 2012, shutting some oil industry operations until the government intervened.
The Norwegian United Federation of Trade Unions wants a pay deal that will maintain employees' purchasing power and improved pension rights, while employers are worried that the country's industry is becoming less competitive internationally. (Reporting by Terje Solsvik and Camilla Knudsen; Writing by Gwladys Fouche; Editing by Greg Mahlich)