PARIS--The European Aviation Safety Agency today issued temporary guidance to airline requiring them to have two crew members in the cockpit at all times in response to Tuesday's Germanwings plane crash.

The updated policy requires at least one qualified pilot to be in the cockpit, Cologne-based EASA said in a statement.

Germanwings Flight 9525 crashed in the French Alps on Tuesday with 150 people on board, with a French prosecutor saying Thursday that it appeared the co-pilot, Andreas Lubitz , had a "willingness to destroy this aircraft."

Europe didn't require airlines to have two qualified pilots in the cockpit at all times, but some airlines have introduced the rule following revelations that the co-pilot of the Germanwings flight had locked himself in the cockpit and didn't allow the pilot to enter and reverse course. The German Aviation Association said Friday that German airlines would introduce the rule.

EASA said it could update the recommendation depending on what additional findings come from the accident probe.

Deutsche Lufthansa AG (LHA.XE) today joined other carriers in revising its policy that allowed the pilot or co-pilot to remain alone in the cockpit.

Write to Robert Wall at Robert.Wall@wsj.com

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