Jan 30 (Reuters) - Petrochemicals maker LyondellBasell LYB.N on Friday posted a surprise loss for the fourth quarter and said it aims to save $1.3 billion by the end of 2026, as it continues to keep a tight lid on costs amid volatility in feedstock and energy prices.

LyondellBasell's shares, however, rose 1.5% in premarket trading as the company said it expects to generate an additional $500 million of cash flow this year.

Chemicals companies have been struggling due to weaker demand and rising raw material costs in key markets such as Europe, where the rigorous regulatory landscape has compelled businesses to reassess their approach in the region.

Last year, LyondellBasell said it would sell four European assets and was planning brief shutdowns at plants in Germany and Texas for maintenance and market alignment.

During the reported quarter, higher feedstock and energy costs coupled with lower prices for its products led adjusted core profit at LyondellBasell's olefins & polyolefins-Americas unit to drop by 67% to $164 million.

Olefins are used to manufacture polymers such as plastic.

Meanwhile, adjusted core profit in the intermediates & derivatives segment, which makes oxyfuels and intermediate chemicals, fell 18% to $205 million from a year ago.

The company posted an adjusted loss of 26 cents per share for the quarter ended December 31, compared with analysts' estimate of a profit of 13 cents per share, according to data compiled by LSEG.

(Reporting by Pranav Mathur in Bengaluru; Editing by Shailesh Kuber)

((Pranav.Mathur@thomsonreuters.com;))