US President George W Bush, his wife Laura and Secretary of State Condoleezza Rice arrived in the Romanian capital Bucharest Tuesday evening ahead of a NATO summit, according to dpa. Following the official opening of the summit Wednesday evening, Bush is scheduled to give a speech at a conference and then travel to the Black Sea resort of Neptune to hold talks with his Romanian counterpart Traian Basescu. Bush arrived in Romania from NATO candidate Ukraine and he plans to travel on to another potential member of the alliance, Croatia, after the summit ends Friday. The Romanian government views Bush's visit as an indication that the United States is attaching more importance to the Black Sea region, where it has stationed troops since the summer of 2007. The leaders of the 26 NATO member states are expected in Bucharest for this week's summit, which will be policed by 10,000 officers. The summit has been overshadowed by Russian objections to NATO membership for former Soviet republics Ukraine and Georgia and plans by Washington to set up a missile defence shield in former Soviet satellites Poland and the Czech Republic. Bush said in Kiev Tuesday that his state visit to Ukraine was "a clear signal ... that Ukrainian membership (in NATO) is in our interest." He also tried to reassure Moscow that the planned missile defence system was not a threat, saying Russia could easily destroy the radar station in the Czech Republic and missile silos in Poland with its arsenal of weapons. Bush reiterated that the defence shield was to protect against missile threats to Europe from the Middle East. NATO membership for Albania and Macedonia also hangs in the balance. Only Croatia is certain to be invited to join the alliance at this week's summit. Other subjects to be discussed will be troop deployment in Afghanistan and the missile defence shield. Bush and Russian President Vladimir Putin are due to meet in the Russian Black Sea resort of Sochi this weekend, and they could sign a bilateral agreement on Sunday, the official RIA Novosti news agency reported Tuesday. "Experts are working hard on a document within the strategic framework of Russian-US cooperation," the agency cited a Kremlin source as saying. "(The presidents') joint statement will include provisions on missile defence." The source also told the agency that the two outgoing presidents would agree on "a road map" for future Russian-US relations. Putin hands over the Russian presidency to Dmitry Medvedev in May, and the US elects a new president in November after Bush ends his second and final term in office. Washington has recently offered to allow Russian inspectors onto the Central European sites. Prague and Warsaw say they are ready to sign agreements with the US to set up the sites.