Transport minister John Hayes has pledged to double the number of ships flying the UK flag.

Hayes made the commitment, suggesting it would spur the wider UK maritime industry, as he officially opened London International Shipping Week at the city's stock exchange this morning.

"Today I'm pleased to commit to a target," he said, shortly after officially launching the trading day.

"I want to commit today to more that doubling the size of the UK fleet, the ships proudly flying the British flag, from the 14 million tons it was two years ago to 30 million tons."

Hayes says he has given the UK shipping register the resources it needs to achieve that target.

"It will of course be a challenge but I'm sure it's both a worthwhile challenge and one we can meet."

Hayes says hitting the target will put the country back among the top 15 shipping nations on earth with respect to their flag.

"It will increase the number of ships brokered here, insured here, sailing from here," he said

"I'm thrilled today to be able to confirm that and challenge all those who will make that happen to do so."

John Haynes made the pledge at the London Stock Exchange today. Photo: LISW