BAGHDAD (Reuters) - The United Nations has offered to help  solve the problem  between the Iraqi government and the Kurdistan Regional Government (KRG) over a Kurdish independence referendum held on Monday, the Iraqi foreign ministry said on Thursday. Jan Kubis, the top UN envoy in Iraq, made the offer at a meeting with Foreign Minister Ibrahim al-Jafari in Baghdad, the ministry said in a statement. Baghdad plans to impose punitive measures on the KRG in retaliation for holding the vote. It has given the KRG until Friday to hand over control of its international airports or face a ban on direct international flights to and from the Kurdish region. 