TOKYO, June 18 (Xinhua) -- Japan on Tuesday strongly encouraged Iran to abide by a 2015 nuclear agreement after Tehran may exceed the uranium stockpile limit set in the accord.

"We'd like to strongly encourage Iran to abide by the nuclear agreement," Deputy Chief Cabinet Secretary Yasutoshi Nishimura told a press briefing on the matter.

"We are seriously concerned about the escalating tensions in the Middle East. We will keep contact with the United States and Iran and play our role in reducing the tensions and stabilizing the situation," Nishimura added.

Nishimura's comments followed Iran saying a day earlier it may exceed the uranium stockpile limit set in the 2015 accord.

Japanese Prime Minister Shinzo Abe during a two-day trip to Iran last week sought to mediate a deescalation in tensions between Washington and Tehran and offered to broker dialogue between the two countries, but his bid was rejected by Iran, government officials here said.

After his talks in Iran, Abe said that Japan remained committed to working towards the achievement of peace and stability in the region and the deescalation of tensions between the United States and Iran, but noted the situation remained difficult.

Following U.S. President Donald Trump pulling the United States out of the nuclear accord inked in 2015 between Iran and six major powers and restoring sanctions on Iran, Tehran said it planned to keep more enriched uranium than is permitted under the pact.

This lead to the United States sending a carrier strike force, B-52 bombers and armed troops to the Gulf, as tensions mounted. The United States has since sent a further 1,000 troops to the Middle East.

Abe has stressed the need for accidental military skirmished to be avoided, particularly as tensions have escalated further following two oil tankers being attacked near the Strait of Hormuz, one of which was Japanese.

Resource-poor Japan is the world's fourth-largest oil importer and relies on the Middle East for the majority of its crude oil.