London - Letters published by the UK's Iraq War Inquiry show that then-prime minister Tony Blair assured US president George W Bush of his support for regime change in Iraq eight months before the US-led invasion began in March 2003.In a six-page memo to Bush, Blair says he would do "whatever" with regards to removing Iraqi dictator Saddam Hussain. The July 28, 2002, letter is marked "Secret Personal." In it, Blair says toppling Saddam is "the right thing to do" and says the vital question is "not when, but how".At the time, Blair was telling the British public and Parliament that no decision to go to war had been made."I will be with you whatever," Blair wrote his US counterpart. "But this is the moment to assess bluntly the difficulties. The planning on this and the strategy are the toughest yet. This is not Kosovo. This is not Afghanistan. It is not even the Gulf War."Blair was blunt about the lack of public and political support in Britain for an invasion of Iraq."Opinion in the U. is quite simply on a different planet from opinion here in Europe or in the Arab world," he said. "In Britain right now I couldn't be sure of support from Parliament, party, public or even some of the Cabinet. And this is Britain. In Europe generally, people just don't have the same sense of urgency post 9/11 as people in the US."Blair tries to convince a reluctant Bush that the best way to build support would be to take the issue to the UN Security Council. He suggests that by going to the UN, they could give Saddam a deadline to let UN weapons inspectors in without any conditions."He would probably screw it up and not meet the deadline, and if he came forward after the deadline, we would just refuse to deal," Blair wrote.Blair, however, seemed confident he could eventually win public backing by emphasising the threat posed by Saddam."If we recapitulate all the WMD (weapons of mass destruction) evidence; add his attempts to secure nuclear capability; and, as seems possible, add on al-Qaeda link, it will be hugely persuasive over here," he wrote.No weapons of mass destruction were found inside Iraq.Retired British civil servant John Chilcot, who oversaw the seven-year Iraq War inquiry, released a damning report Wednesday, saying "the UK chose to join the invasion of Iraq before the peaceful options for disarmament had been exhausted. Military action at that time was not a last resort."By the time British combat forces finally left Iraq in 2009, the conflict had killed 179 British troops, almost 4 500 American personnel and more than 100 000 Iraqis.