London (CNN Business) Lufthansa's stock plummeted Monday after the German carrier warned that intense competition from low-cost European rivals was hurting its bottom line.

Shares in the airline dropped more than 12% in Frankfurt to €15.47 ($17.35), their lowest level in over two years.

Lufthansa DLAKF on Sunday issued a profit warning, downgrading its expected margins for 2019 to between 5.5% and 6.5% from an earlier estimate of 6.5% to 8%.

The airline said that it was facing intense price competition on short flights within Europe from budget airlines that are more concerned with growth than profit margins.

Lufthansa said in a statement that yields, especially in Germany and Austria, "are affected by sustained overcapacities caused by carriers willing to accept significant losses to expand their market share."

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