FRANKFURT, May 11 (Reuters) - A shortage of dye for medical scans produced by General Electric's healthcare unit in China is affecting regions beyond the United States with a German hospital warned of a supply squeeze.

GE Healthcare, through a spokesperson, said on Wednesday that the weeks-long outage at the company's Shanghai production plant due to the city's COVID-19 lockdown is not only affecting U.S. hospitals but also other world regions it did not specify, though to a less extent.

Some of the largest U.S. hospitals have prepared this week for critical shortages and the GE unit has responded by increasing output of contract agents at its factory in Ireland and sending products by air freight to meet demand.

The association of German hospitals told Reuters on Wednesday that one of its members had been alerted by the GE unit that its contrast agent could go out of stock in June, citing the Shanghai outage.

A hospitals association spokesperson did not provide further details and said it was uncertain whether diagnostics procedures would have to be cancelled or to what degree the affected hospital could draw on inventories.

"We are working around the clock to expand capacity of our iodinated contrast media products, including drawing on our global manufacturing network," the GE spokesperson said, adding the business would keep customers informed.

GE said this week the Shanghai facility has now reopened after several weeks of closure due to local COVID policies but is not yet fully up to speed.

Bayer, which competes with GE Healthcare in contrast media, has said it is not facing a similar situation and that it was taking measures to supply "incremental volumes" to ease shortages. (Reporting by Ludwig Burger; Editing by Kirsten Donovan)