General Motors Co will focus on maintaining profits, not defending U.S. market share gains made at the expense of Japanese rivals, the automaker's top executive said on Monday.

I like profitability more than I do market share, Chief Executive Dan Akerson said at the Detroit auto show. We're a mass producer and scale matters to us, but obviously we'll look for margin and profitability going into 2012.

Akerson pointed out that GM has increased its share of the U.S. market two straight years, the first time it has done that since 1977.

Prior to its 2009 bankruptcy, GM was criticized for loading incentives onto its cars to drive sales and keep its factories operating at high capacity, regardless of what that did to profits. Since its restructuring, GM executives have stressed protecting the company's fortress balance sheet.

GM's share of the U.S. market rose to 19.6 percent last year from 19.1 percent in 2010, according to research firm Autodata. Toyota Motor Corp's <7203.T> share fell 2.3 points to 12.9 percent, and Honda Motor Co Ltd's <7267.T> slipped 1.6 points to 9 percent due to the tsunami in Japan last March.

Many in the industry have focused on the race between GM, Toyota and Germany's Volkswagen AG for the global sales title.

I don't know if we ever set out a goal to achieve being the largest manufacturer in the world, Akerson told reporters.

GM North American chief Mark Reuss said the big challenge for GM this year will be retaining last year's market share gains.

What we're really going to focus on is retaining our customers, but not at the expense of profits, he told Reuters Insider.

Eroding residuals for new cars like the ATS or the Sonic or the Cruze is really not about what we're going to do, he added, referring to the new Cadillac ATS and two Chevrolet cars. We're in it for the long term.

Reuss added GM's U.S. consumer incentives will remain at or near the industry average.

(Reporting by Ben Klayman; editing by John Wallace)