Leaders of ruling and opposition parties on Saturday stressed that local, provincial and federal elections should be held on time to ensure Constitution implementation.Speaking with journalists at a tea party hosted by the main opposition, CPN-UML, on the occasion of Dashain, Tihar, Nepal Samvat New Year and Chhath festivals today, Nepali Congress President Sher Bahadur Deuba and UML Chairman KP Sharma Oli said elections were a must to implement the new charter. The two top leaders, Deuba and Oli, however, did not express clear views on the much-hyped issue of Constitution amendment. While Deuba commented that the UML was not against Constitution amendment, but just wanted a valid reason for the same; Oli refused to make political comments as the tea party was organised just to exchange festive greetings. The main opposition had invited leaders of major parties at the function organised at the local Shankhapark, in front of its central office, in Dhumbarahi. Prime Minister and CPN Maoist Centre Chairman Pushpa Kamal Dahal, however, was absent in the informal, but significant, political gathering as he had just left for India for the BRICS-BIMSTEC Outreach Summit this morning.