Helsingborg, May 22 -- In an unexpected policy shift, US President Donald Trump has promised North Atlantic Treaty Organisation (NATO) partners to deploy an additional 5,000 personnel to Poland. However, US Secretary of State Marco Rubio has warned alliance ministers that Washington's "disappointment" with certain members remains an unresolved issue that demands future deliberation.

The sudden influx of troops effectively reverses recent anxieties in Warsaw, where Polish officials had been deeply unsettled by intelligence indicating that the Pentagon had scrapped plans for a rotational deployment involving roughly 4,000 American soldiers.

Addressing reporters on Friday during an assembly of NATO foreign ministers in the Swedish town of ...