By Clement Uwiringiyimana KIGALI (Reuters) -Rwanda will retaliate if it suffers further attacks from neighbouring Democratic Republic of Congo, its foreign minister said on Tuesday, after accusing Congo of firing shells across the border earlier this month. Congo summoned Rwanda’s ambassador and suspended RwandAir flights to Congo over the weekend in response to what it said was Kigali’s support for M23 rebels carrying out a military offensive in its eastern borderlands. Rwanda denies the claims and has in turn accused Congo’s army of fighting alongside the Democratic Forces for the Liberation…