LONDON, July 23 (Reuters) - The Swedish-based operator of the British-flagged tanker seized last week by Iran said on Tuesday it was still awaiting permission to visit the ship's 23 crew members.

"We continue to focus our efforts on supporting the families of those affected in India, Russia, Latvia and the Philippines and will continue to offer full support until all 23 crew members are released and safely back with their families," it said in a statement.

Stena Bulk added that all necessary notifications had been made for the Stena Impero’s transit of the Strait of Hormuz, which it said was carried out in full compliance with all international maritime regulations.

"We can confirm that we are not aware of, and nor is there any evidence of a collision involving the Stena Impero," it said.

On Saturday, Iran said the tanker was seized because it had collided with a fishing boat. (Reporting by Stephen Addison Editing by William Schomberg)