Going quiet is ordinary and rarely indicates a problem with the engagement. A busy period, a decision requiring somebody who was not in the conversation, waiting on content you have not had time to produce, or something entirely unrelated arriving. None of those need explaining and all of them look identical from the outside, which is the only genuine difficulty.
Say something rather than nothing, which is the one thing that actually helps. A message saying you need three weeks converts an unknown into a date, and the work can be scheduled around it. The alternative is a series of follow ups that feel like chasing to both parties and produce nothing except mutual discomfort.
Expect follow up rather than escalating pressure. A check in after a week, another after two, and then a message asking whether the timing has changed and offering to pause formally. That sequence is designed to make responding easy rather than to apply pressure, and somebody who has been avoiding the conversation because they have no answer is given a way to say so.
What happens practically is that completed work is finished and delivered rather than left partial. Accounts are in your name from the day they are created, decisions are documented, and anything paid for is yours. Resuming starts from a written position rather than from two different memories of where things stood.
The cost is the schedule rather than the money. A pause does not accrue charges and it does mean the slot moves. Re entering a schedule takes whatever the next availability requires, which is frequently longer than the pause itself, and that is a capacity constraint rather than a penalty.
The awkwardness is usually the actual obstacle, which is worth naming. Businesses go quiet, feel embarrassed about the silence, and then find the embarrassment makes responding harder as time passes. That spiral is common and entirely avoidable with one sentence, and nobody on the receiving end is keeping score.
Consider whether the pause is actually a stop, which is a legitimate outcome and better named than avoided. Circumstances change and a project that no longer makes sense should end rather than sitting as an open commitment. Saying so clears it for both parties and preserves the relationship considerably better than indefinite silence.
Then set a check in date rather than leaving it open, even approximately. Open ended pauses tend to become quiet endings, and a date is what prevents a project everybody still wants from lapsing by accident.
Set an expectation about follow up at the start, since knowing that a check in arrives after a week removes the sense that silence is being judged. That single arrangement prevents most of the discomfort that makes going quiet worse than it needs to be.
Say what you need rather than only that you are busy, since a specific request is easier to act on. Needing a fortnight, needing a smaller first phase, or needing to defer until a particular event are all workable, and the general statement is what leaves both parties guessing.
Consider whether the silence is about the project or about something else, since a business under pressure elsewhere frequently withdraws from everything at once. Saying that plainly usually produces more accommodation than people expect, and it prevents the project being read as the problem.