US President Barack Obama has already agreed to the “toughest sanctions” ever on Iran in a bid to punish the country for its continued efforts to build what Iran is claiming to be peaceful nuclear capabilities. The American head of state defended his decision saying it was very important to remember, particularly given some of the political noise out there, that this administration has “systematically imposed the toughest sanctions on Iran ever,” Obama told reporters. Observers argue this is a move to attract the more conservative elements of the American electorate who favour belligerent speech and who remain deeply hostile to the Islamic republic. “When we came into office the world was divided. Iran was unified and moving aggressively on its own agenda,” he said. “Today Iran is isolated and the world is unified and applying the toughest sanctions that Iran’s ever experienced, and (that) is having an impact inside of Iran.” The United States and Israel have not ruled out military action against Iran\'s nuclear facilities if diplomacy fails to resolve a dispute over a programme they suspect is aimed at developing atomic weapons. Tehran denies any such ambition and says the programme is for peaceful civilian energy and medical purposes only. “Iran understands that they have a choice,” Obama said. “They can brave that isolation by acting responsibly and foreswearing the development of nuclear weapons which would still allow them to pursue peaceful nuclear power... or they can continue to operate in a fashion that isolates them from the entire world,” he said. “And if they are pursuing nuclear weapons, then I have said very clearly that is contrary to the national security interests of the United States, it is contrary to the national security interests of our allies, including Israel, and we are going to work with the world community to prevent that.” To add to Iran’s isolation Japan joined on Friday the Western fray by toughening sanctions on the country. It said it added around 100 Iranian groups and an individual to a blacklist that imposes asset freezes and now totals over 300 entities. It also raised the number of Iranian banks it has suspended correspondent banking relationships with to 20 from 17. Japan\'s move does not include ramping up its restrictions on Iran\'s energy sector even after the EU laid out plans for a possible oil embargo and the US last month expanded sanctions to target companies that aid Iran\'s oil and petrochemical industries.  Measures announced by Japan in September 2010 included halting all new energy-related investment in Iran and warning companies to be cautious over existing contracts. Japan is the third biggest buyer of crude oil from Iran, OPEC\'s second largest producer, after China and India. Tensions with the West rose after hardline students stormed two British diplomatic compounds in Tehran last week in protest against new sanctions imposed after the UN nuclear agency suggested that Iran was pursuing nuclear weapons. However others argue war on Iran has already been declared in a covert fashion over the past year already. Several nuclear scientists have been killed in mysterious circumstances and Iranian nuclear facilities have faced a barrage of cyber attacks, seriously hindering the work of the plants. An unexplained explosion in a military base in Iran last month killed 17 soldiers and other explosions were reported in Isfahan, in central Iran, a few days later. While no government has admitted its involvement, some say these point to a new form of warfare that will avoid full scale conflict while seriously affecting Iran’s capabilities and seriously destabilising the regime. As the call for war intensifies from Western capitals it appears that ‘soft war’ has to some extent already begun.