TOKYO, May 16 (Xinhua) -- Japan on Thursday expressed its concern over mounting tensions in the Persian Gulf related to hostilities between the United States and Iran over an international nuclear agreement.

At the outset of a meeting with visiting Iranian Foreign Minister Mohammad Javad Zarif, Japanese Prime Minister Shinzo Abe said the issue has become increasingly tenser.

"We are concerned that the situation in the Middle East is getting extremely tense," Abe was quoted as saying at the start of their talks, adding that Japan wanted to continue to maintain and develop amicable ties with Iran.

Zarif, for his part, said that the two countries are very important partners and have traditionally had friendly ties. He said it was necessary due to the current situation to discuss with Abe a number of relevant issues.

Abe, meanwhile, said that it was his hope that Iran would stick to an international nuclear accord inked in 2015, to which Zarif said that Iran's countermeasures do not run contrary to the framework of the pact.

Zarif's visit to Tokyo came following the United States sending a carrier strike force and B-52 bombers to the Gulf after Iran said it plans to keep more enriched uranium than is permitted under the pact.

In response, Iran said that it would suspend some of its commitments under the deal, of which the United States pulled out of in 2018.