(Reuters) - Frontier Group ( ULCC ), the parent of Frontier Airlines, withdrew its full-year forecast on Thursday and warned of a loss in the first quarter, as U.S. President Donald Trump's trade war has hit travel demand.

The Denver-based company is the second major U.S. carrier to ditch its forecast after Delta Air Lines ( DAL ) pulled its full-year guidance on Wednesday.

Frontier said travel demand has weakened, resulting in fare discounting and promotions across the industry. Citing the uncertain environment, the airline said it was unable to reaffirm the full-year 2025 outlook.

In February, the company had forecast an adjusted profit of at least $1.00 this year, and breakeven earnings of 7 cents a share in the March quarter.

Trump's trade war has rattled global markets, hitting business and consumer confidence. As travel is a discretionary item for many consumers and businesses, mounting economic worries have clouded the airline industry's outlook and sparked a selloff in shares.

Weakening consumer demand has also undermined the industry's pricing power. Airline fares fell 5.3% in March from a month ago, posting their steepest monthly decline since September 2021, according to data from the U.S. Labor Department.

Frontier's shares fell about 12.5% on Thursday and have shaved off half their value so far this year.

Shares of Southwest ( LUV ), Alaska, Delta, United and American Airlines ( AAL ) fell between 10% and 14% on Thursday.

The S&P 1500 Airlines index is down about 37% so far this year, compared with the wider S&P 500's 10.43% drop.

Battered global markets and anxious global leaders welcomed Wednesday's reprieve when Trump suddenly decided to freeze most of his hefty new duties for 90 days. But the selloff resumed on Thursday amid fears of a worsening trade war with China.

Frontier said it expects a modest 5% revenue growth in the first quarter, adding it would continue to monitor demand and adjust capacity as needed.

It has cut capacity, or the seats available on flights, for the June quarter to avoid lowering fares and protect margins. It now expects a low single-digit year-on-year decline in capacity in the second quarter.

Frontier expects an adjusted quarterly loss in the range of 20 to 24 cents per share, compared with analysts' average estimate of a loss of $0.03 per share, according to data compiled by LSEG.

The company will report its quarterly earnings on May 1.