London, May 12 (IANS): British Prime Minister Theresa May has told US President Donald Trump that her government remains firmly committed along with her European partners to maintain the Iran nuclear deal, media reported on Saturday.

During a phone call on Friday, May said she was "firmly committed to ensuring the deal was upheld, as its the best way of preventing Iran from developing a nuclear weapon", Xinhua News agency reported quoting Downing Street spokesperson.

May raised the potential impact of US sanctions on those firms which were currently conducting business in Iran.

The two leaders also condemned the Iranian rocket attacks against Israeli forces earlier this week and agreed on the need for calm on all sides.

The spokesperson said May and Trump also discussed the relations between the US and North Korea, as May began the call by congratulating Trump on the safe return of three US citizens who had been held in North Korea.

"The two leaders looked forward to the summit which will take place between President Trump and Kim Jong-un in Singapore," the spokesperson said, adding that Britain would continue to work with the US to keep up the pressure for denuclearisation of North Korea.

According to the spokesperson, May and Trump were looking forward to Trump's visit to Britain in July.