LISBON--Banco Comercial Portugues SA (BPCGY, BCP.LB) said Monday that it swung to a first-quarter net loss, hampered by higher provisions for past-due loans and a loss from its recently sold Greek unit.

Portugal's second-largest bank by market value reported a net loss of 152 million euros ($198.6 million) in the first quarter, compared with a EUR40.8 million net profit reported in the same quarter the year before. The result was largely in line with the EUR153.1 million expected by a Dow Jones Newswires poll of three analysts.

The bank's bottom line was hurt by a negative contribution from its operations in Greece, which were sold in April to Greece's Piraeus Bank SA (TPEIR.AT). The transaction will enable BCP to deconsolidate about EUR4 billion of right-weighted assets of its unit, it said. According to BCP, its net loss excluding Greek operations would have been a narrower EUR109.7 million.

BCP also said bad-debt charges rose to EUR188.4 million from EUR152.3 million, as the country's austerity measures continue to pressure loan books and to force banks to set aside more money to cover souring loans. The ratio of credit at risk stood at 13.8% of total loans at the end of March, from 10.9% the year before.

Portugal's economy is expected to slump 2.3% this year, bending under the pressure of a belt-tightening effort related to a EUR78 billion international bailout.

The bank's net interest income--the difference between interest paid on deposits and those charged on loans--fell to EUR183 million from EUR309.4 million, including a EUR66.6 million cost of borrowing money from the Portuguese government in the form of contingent convertible bonds.

The so-called CoCos are sold as interest-bearing debt that has to be paid back, and were part of BCP's recapitalization plan.

The bank also said its trading profit tumbled to EUR74.7 million, from EUR174 million a year earlier.

The bank's core Tier 1 capital ratio stood at 9.6% as of March 31, according to requirements set by the European Banking Authority.

-Write to Carla Canivete of Webtexto at carla.canivete@dowjones.com

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