* Deal flow slow so far this year
* Falls to loss on investments, higher costs
* Stock down 1.8 pct
TORONTO, May 10 (Reuters) - Onex Corp, one of Canada's biggest private equity firms, fell to a net loss in the first quarter, but said on Friday it is seeing acquisition opportunities in Europe one year after opening an office in London.
The opportunities in Europe come as North American deals have been hard to come by early this year, Chief Executive Gerry Schwartz said on a conference call with analysts and investors.
While Onex made five acquisitions worth a total of $1.5 billion in the fourth quarter of 2012, it has announced just one deal so far this year, the $950 million acquisition of the trade show business of Nielsen Holdings NV unveiled earlier this week.
"It seems that many business leaders have been holding on to their existing assets, and are reluctant to sell even non-core assets," said Schwartz.
Onex opened the London office last summer and has since been adding staff and building relationships. Managing director Anthony Munk said the work is starting to pay off as opportunities surface amid a challenging business environment.
"There's clearly a number of financial sponsors who are owners of businesses that are finding it challenging to take those companies public and as a results they're pursuing the outright sale of those businesses," Munk said.
He said Onex's areas of interest in the region included industrials, building products, and health care.
Toronto-based Onex owns stakes in several companies, including electronics manufacturer Celestica Inc and Spirit Aerosystems, as manages a handful of private equity funds.
It has about $1.3 billion in cash and near-cash items, and will begin fundraising for its Onex Partners IV fund later this year.
FALLS TO LOSS
Onex lost $271 million, or C$2.71 a share, in the three months ended March 31, compared with a profit of C$173 million, or 51 cents in the year-before period.
Revenue rose 6 percent to $7.2 billion. However, cost of sales and operating expenses both rose, while the net increase in value of investments in joint ventures and associates fell 55 percent to C$276 million.
The company's shares were down 1.8 percent at C$49.07 on the Toronto Stock Exchange.