Harare – Zimbabwean opposition politicians have reportedly said that a wheel chair that was given as a gift by Cabinet minister to President Robert Mugabe was proof that the nonagenarian was "too old and unfit" to rule. Cabinet ministers on Monday presented a mobile chair to Mugabe to "enable him navigate his way around his office as well as at home".The mobile chair, otherwise ordinarily referred to as a wheelchair, was presented as a belated birthday gift during a ceremony at his office. Critics said it confirmed that old age had taken its toll on the Zanu-PF leader who turned 93 in February.According to New Zimbabwe.com, Movement for Democratic Change Secretary General Douglas Mwonzora said that the gift was an indication that the nonagenarian was no longer fit to continue ruling the Southern African country."The special chair is a clear admission that Mugabe is now physically and mentally unfit and we can no longer allow him to govern. He should simply resign," Mwonzora was quoted as saying. Zapu spokesperson Iputhule Maphose concurred, saying that the veteran leader should "simply resign". Mugabe has been at the helm of the country for the past 37 years.His ruling Zanu-PF party has endorsed him to be the party’s presidential candidate at next year’s polls tentatively set for July.