* Future wage rises, performance pay will depend on profitability
* GM Korea, KDB still need to negotiate terms of financial support
* GM Korea saw $1.1 bln net loss in 2017, 4th straight year in red (Adds details of the deal, lawmaker comments)
SEOUL, April 23 (Reuters) - General Motors Co's (GM) South Korean unit dropped a plan for a vote on a bankruptcy filing after reaching a tentative wage deal with its labour union on Monday that helped the U.S. automaker win concessions on pay, bonuses and benefits.
GM shocked South Korea in February when it unveiled a major restructuring plan for the money-losing unit, which involved shuttering one of its four plants in the country and voluntary redundancies for 2,600 workers.
The automaker had sought wage concessions from the union as well as government funding and incentives to save its remaining three South Korean factories.
The board of GM Korea delayed a decision to file for court-managed bankruptcy protection until Monday evening, after the automaker had failed to reach a wage deal with its labour union in time to meet a Friday deadline.
"Through the latest agreement, GM Korea will be a competitive manufacturing company," Kaher Kazem, chief executive of GM Korea, said in a statement in Korean.
The deal would pave the way for the Korea Development Bank (KDB) to provide support and for GM to allocate new models to South Korea to help turn around GM Korea, the unit said in a statement.
KDB is GM Korea's second-largest shareholder with a 17 percent stake. The U.S. automaker owns 77 percent of GM Korea, while GM's main Chinese partner, SAIC Motor Corp Ltd , controls the remaining 6 percent.
The government had stepped up pressure on GM and the union to reach an agreement, saying without a swift deal some 150,000 jobs at the automaker and its suppliers would be at risk.
GM Korea still needs to negotiate with KDB on terms of the latter's financial support to the unit, while trying to secure tax and other incentives from the industry ministry.
KDB's chairman told Reuters last week the lender may sign a preliminary agreement by April 27 to provide financial support for the business should an interim due-diligence report that was due last Friday turn out to be satisfactory. The status of the report could not be immediately ascertained.
The union accepted the company's request to freeze base wages and skip bonuses for this year as well as trim benefits.
Future base wage increases and performance pay "will be dependent upon the company regaining profitability", while the base wage rises will not exceed inflation, according to the agreement seen by Reuters.
Regarding its 680 remaining workers at the Gunsan factory, which is scheduled to be shuttered in May, the company will "implement options including a voluntary redundancy program and transfers" to other plants to avoid layoffs.
"The labour union made huge concessions to save the company," Hong Young-pyo, a lawmaker of the ruling Democratic Party who mediated the agreement, said at a news conference after the deal.
The union was absent from the press conference where Hong and GM executives were present.
A union spokesman declined to comment, saying union members are expected to vote on the preliminary deal on Wednesday and Thursday.
Over the past three years, GM has sought to focus on profitable markets, mainly the United States and China, and new technologies such as electric and automated vehicles.
The South Korean unit, once the backbone of GM's Asian strategy, has been hobbled by labour costs and hurt by the automaker's decision to pull its Chevrolet brand from Europe, a key export market. It posted a net loss of $1.1 billion in 2017, its fourth straight year in the red.
The unit still makes more than 1 million assembled or partially assembled vehicles for the United States, European and emerging markets. It is also an engineering and design source for GM's small vehicles and electric vehicles, as well as home to some of GM's top-ranked suppliers globally.
(Reporting by Hyunjoo Jin; Additional reporting by Ju-min Park and Haejin Choi Editing by Jacqueline Wong and Muralikumar Anantharaman)