I do not think so. The ICSID will press on regardless. What can suspend ICSID proceedings though is not paying fees and expenses for the proceedings when due as each side is expected to do. The fees are costly. Annual dues expected and on time, secretarial, commitee members expenses, etc, etc. from the ICSID side. And the list goes on.
Several arb proceedings have been suspended and concluded due to lack of payment of costs by the claimant to the ICSID.
One not so good clause in the ICSID rules is that the respondent may file an appeal and that takes 2 years to react to it.