DUBAI: The UAE will impose a minimum top-up tax (DMTT) of 15 percent on large multinational companies operating in the country starting in January, the finance ministry said on Monday as the government seeks to boost non-oil revenue. The DMTT is part of the OECD’s global minimum corporate tax agreement which has 136 signatories, including the UAE, to ensure big companies pay a minimum 15 percent and to make tax avoidance harder.