Mae Prif Weinidog Cymru, Carwyn Jones, wedi rhoi rhybudd clir heddiw fod y cyfleoedd economaidd fydd ar gael ar ôl Brexit yn cael eu tanseilio gan ansicrwydd a chan ddiffyg trefn Llywodraeth y Deyrnas Unedig wrth fynd ati i negodi.
First Minister Carwyn Jones has today issued a stark warning that economic opportunities post-Brexit are being undermined by uncertainty and a chaotic approach to negotiations by the UK Government.