Karim, who has been nominated by parliament's third largest political grouping, told MEPs that the office of president should "rise above partisan politics and ordinary political ambition".
He was critical of the role being considered, "A counter in a game. A consolation prize for failing to get a consolation prize. Plan D in a political life when plans A, B and C have failed."
"We were told in the recent election that 'this time it would be different': that transparency would prevail over secrecy, that principle would override expediency, that honest, democratic politics would triumph over the backward-looking, backroom deal.
"But sadly, just a few weeks after the European election, we are being invited to endorse a cosy consensus, brokered behind closed doors."
"The president should reflect the diversity of this house, as this house reflects the diversity of the peoples of Europe" - Sajjad Karim
The 'stitch-up' agreement to divide the parliament presidency between the EPP and S&D - parliament's largest political groupings - has drawn criticism from other political stripes, including Greens/EFA candidate Ulrike Lunacek.
The Austrian deputy said, "To simply endorse a candidate that has been chosen as part of a backroom deal by EU governments, with no scrutiny, would set this legislative term off on the totally wrong foot.
"It would also fundamentally undermine the trust placed in the European parliament by voters."
Karim also expressed his concern over any potential politicisation of the role of parliament president, and warned against the post being used to "express personal opinions", "promote personal interests" or being used to "advance [a] personal career".
"The president should reflect the diversity of this house, as this house reflects the diversity of the peoples of Europe. The president should be fair to all, open to all, attentive to all."
President of the ECR group Syed Kamall also delivered a last minute press briefing ahead of the plenary session, where he underlined his MEPs' role as a "growing force" that would "challenge the cosy consensus and institutional navel gazing".
"We must look forward" - Syed Kamall
Addressing journalists, Kamall also announced that UK ECR deputy Vicky Ford would chair the internal market and consumer protection committee and that former Polish foreign minister Anna Fotyga would head up the security and defence sub-committee.
The ECR group chief spoke out against a "Brussels village that tends to look back all the time," adding that reformist MEPs had a duty to "look forward and challenge the cosy post-war consensus of the 1950s".
"Where we object we will oppose, " said Kamall, but stressed that his group would "work with reformers", including commission presidency candidate Jean-Claude Juncker, if ideas were presented that supported the ECR's reform programme.
Kamall underlined the lack of voter concern over issues such as the spitzenkandidaten process - which he said was based on a "tenuous reading of the Lisbon treaty" - and inter-institutional relations.
He said he intended for his group to focus on issues that genuinely concern European citizens, such as "chronic unemployment" and the "completion of the single market".
"We must look forward," he concluded.